To each his own....I happen to like grip tape. Bought a sheet of it (about 12"x24') at a surf/skateboard shop. Use it on the grip of my Glock 23. I originally put it on both sides of my grip since I was only using it for tactical jump-outs and carried it in a tactical thigh holster. The inside (left) grip didn't make contact with my clothing. Then, when I moved to another squad where suits/sportcoats were the order of the day, I started carrying my G-23 in my pancake holster. It started to make my shirt get all frayed, so I took it off the inside (left) grips. Still gives me a better, more secure grip with the tape only on the right side, and it didn't leave ANY sticky residue on the left grip when I took it off.
I too, added small strips (about 1"x1/2") of the grip tape to the bottom sides (4 total) on each of my 30rd magazines for my carbine. I personally don't like magpuls, and this makes gripping/grasping the mags very secure. Since the bottom of the mags stick out of the mag pouches, the grip tape is what I grasp. Because the strips are only 1" long, they don't interfere with the mag well. I also added 2 or three very small (like about 1/2" wide) strips around the circumference of the vertical grip on my carbine. I have a GG&G vert grip, and the grip strips give it just the right amount of "gripability". Any more tape on the vert grip would make it too rough on the support hand.
Hell, I've even added 4 tiny pieces to the top/sides of my cell phone so that I can better grip/pull it out of the drop-in belt pouch. I got the idea when I saw a small sheet (about 4"x6") of similar stuff packaged for sale in a Radio Shack for around $10.00 per single sheet. I've still got about 8/10's of my original sheet of skateboard tape left for future projects!!