Chrome is nice, but in civilian life it really isn't necessary. Are you going to be in the swamps of Alabama shooting corrosive ammo for weeks on end, without cleanings? If not, then chrome isn't absolutely necessary. Its nice, but most don't "need" it.
Do you know how many military weapons don't use chrome lined barrels? And they aren't just AK's and SKS's from Yugoslavia.
In many cases, chrome lining is only around 30.00-50.00 more. That's really not alot of extra money. While you may not "need" it, I don't hear many M4gery owners saying "Damn, I wish I didn't get a chrome lined barrel". Its usually the other way around.
Only you can decide need, however for an average civilian rifle chrome is far from necessary. If you shoot non-corrosive ammo*or take precations after shooting corrosive ammo* and take reasonably good care of your gun, you don't need chrome.
Its nice to have certainly, but its far from mandatory for a civvie gun.