Can someone please show me where in the law it says I can not carry during festivals, and street fairs?   Like the St charles Scarecrow fest. It is in St charles but but put on by these people  http://www.visitstcharles.com/AboutUs and these people  http://www.ravenswoodevents.com/. So can I carry there?

Is this what you want?

http://www.ilga.gov/legislation/ilcs/ilcs3.asp?ActID=3497

(430 ILCS 66/65)
   Sec. 65. Prohibited areas.
   (a) A licensee under this Act shall not knowingly carry a firearm on or into:


         (10) Any public gathering or special event conducted on property open to the public that requires the issuance of a permit from the unit of local government, provided this prohibition shall not apply to a licensee who must walk through a public gathering in order to access his or her residence, place of business, or vehicle.

     (11) Any building or real property that has beenissued a Special Event Retailer's license as defined in Section 1-3.17.1 of the Liquor Control Act during the time designated for the sale of alcohol by the Special Event Retailer's license, or a Special use permit license as defined in subsection (q) of Section 5-1 of the Liquor Control Act during the time designated for the sale of alcohol by the Special use permit license.

       (12) Any public playground.

       (13) Any public park, athletic area, or athletic facility under the control of a municipality or park district, provided nothing in this Section shall prohibit a licensee from carrying a concealed firearm while on a trail or bikeway if only a portion of the trail or bikeway includes a public park.

Yep, if the event requires a permit you are banned.

It's easier to list the places you can carry than those you cannot, sadly.

In your state, what happens if he does carry in an unauthorized place?

Link above.  I believe these are the relevant legal sections.   IANAL.

(430 ILCS 66/70)
   Sec. 70. Violations.

(e) Except as otherwise provided, a licensee in violation of this Act shall be guilty of a Class B misdemeanor. A second or subsequent violation is a Class A misdemeanor. The Department may suspend a license for up to 6 months for a second violation and shall permanently revoke a license for 3 or more violations of Section 65 of this Act. Any person convicted of a violation under this Section shall pay a $150 fee to be deposited into the Mental Health Reporting Fund, plus any applicable court costs or fees.

(f) A licensee convicted or found guilty of a violation of this Act who has a valid license and is otherwise eligible to carry a concealed firearm shall only be subject to the penalties under this Section and shall not be subject to the penalties under Section 21-6, paragraph (4), (8), or (10) of subsection (a) of Section 24-1, or subparagraph (A-5) or (B-5) of paragraph (3) of subsection (a) of Section 24-1.6 of the Criminal Code of 2012. Except as otherwise provided in this subsection, nothing in this subsection prohibits the licensee from being subjected to penalties for violations other than those specified in this Act.

And...

(730 ILCS 5/5-4.5-55)
   Sec. 5-4.5-55. CLASS A MISDEMEANORS; SENTENCE. For a Class A misdemeanor:
   (a) TERM. The sentence of imprisonment shall be a determinate sentence of less than one year.
   (b) PERIODIC IMPRISONMENT. A sentence of periodic imprisonment shall be for a definite term of less than one year, except as otherwise provided in Section 5-5-3 or 5-7-1 (730 ILCS 5/5-5-3 or 5/5-7-1).
   (c) IMPACT INCARCERATION. See Section 5-8-1.2 (730 ILCS 5/5-8-1.2) concerning eligibility for the county impact incarceration program.
   (d) PROBATION; CONDITIONAL DISCHARGE. Except as provided in Section 5-5-3 or 5-6-2 (730 ILCS 5/5-5-3 or 5/5-6-2), the period of probation or conditional discharge shall not exceed 2 years. The court shall specify the conditions of probation or conditional discharge as set forth in Section 5-6-3 (730 ILCS 5/5-6-3).
   (e) FINE. A fine not to exceed $2,500 for each offense or the amount specified in the offense, whichever is greater, may be imposed. A fine may be imposed in addition to a sentence of conditional discharge, probation, periodic imprisonment, or imprisonment. See Article 9 of Chapter V (730 ILCS 5/Ch. V, Art. 9) for imposition of additional amounts and determination of amounts and payment.
   (f) RESTITUTION. See Section 5-5-6 (730 ILCS 5/5-5-6) concerning restitution.
   (g) CONCURRENT OR CONSECUTIVE SENTENCE. The sentence shall be concurrent or consecutive as provided in Section 5-8-4 (730 ILCS 5/5-8-4).
   (h) DRUG COURT. See Section 20 of the Drug Court Treatment Act (730 ILCS 166/20) concerning eligibility for a drug court program.
   (i) CREDIT FOR HOME DETENTION. See Section 5-4.5-100 (730 ILCS 5/5-4.5-100) concerning credit for time spent in home detention prior to judgment.
   (j) GOOD BEHAVIOR ALLOWANCE. See the County Jail Good Behavior Allowance Act (730 ILCS 130/) for rules and regulations for good behavior allowance.
   (k) ELECTRONIC MONITORING AND HOME DETENTION. See Section 5-8A-3 (730 ILCS 5/5-8A-3) concerning eligibility for electronic monitoring and home detention.
(Source: P.A. 100-431, eff. 8-25-17.)

(730 ILCS 5/5-4.5-60)
   Sec. 5-4.5-60. CLASS B MISDEMEANORS; SENTENCE. For a Class B misdemeanor:
   (a) TERM. The sentence of imprisonment shall be a determinate sentence of not more than 6 months.
   (b) PERIODIC IMPRISONMENT. A sentence of periodic imprisonment shall be for a definite term of up to 6 months or as otherwise provided in Section 5-7-1 (730 ILCS 5/5-7-1).
   (c) IMPACT INCARCERATION. See Section 5-8-1.2 (730 ILCS 5/5-8-1.2) concerning eligibility for the county impact incarceration program.
   (d) PROBATION; CONDITIONAL DISCHARGE. Except as provided in Section 5-6-2 (730 ILCS 5/5-6-2), the period of probation or conditional discharge shall not exceed 2 years. The court shall specify the conditions of probation or conditional discharge as set forth in Section 5-6-3 (730 ILCS 5/5-6-3).
   (e) FINE. A fine not to exceed $1,500 for each offense or the amount specified in the offense, whichever is greater, may be imposed. A fine may be imposed in addition to a sentence of conditional discharge, probation, periodic imprisonment, or imprisonment. See Article 9 of Chapter V (730 ILCS 5/Ch. V, Art. 9) for imposition of additional amounts and determination of amounts and payment.
   (f) RESTITUTION. See Section 5-5-6 (730 ILCS 5/5-5-6) concerning restitution.
   (g) CONCURRENT OR CONSECUTIVE SENTENCE. The sentence shall be concurrent or consecutive as provided in Section 5-8-4 (730 ILCS 5/5-8-4).
   (h) DRUG COURT. See Section 20 of the Drug Court Treatment Act (730 ILCS 166/20) concerning eligibility for a drug court program.
   (i) CREDIT FOR HOME DETENTION. See Section 5-4.5-100 (730 ILCS 5/5-4.5-100) concerning credit for time spent in home detention prior to judgment.
   (j) GOOD BEHAVIOR ALLOWANCE. See the County Jail Good Behavior Allowance Act (730 ILCS 130/) for rules and regulations for good behavior allowance.
   (k) ELECTRONIC MONITORING AND HOME DETENTION. See Section 5-8A-3 (730 ILCS 5/5-8A-3) concerning eligibility for electronic monitoring and home detention.
(Source: P.A. 100-431, eff. 8-25-17.)