It isnt cool. What - you need to prove your hat is a new hat, and not a used one, or has been worn more than a few times... Jeez...
Here is a article on why...
I recently asked a young person why they left the sticker on their hat, since I was raised in the strange era where we removed stickers and tags before donning our clothing. He responded by suggesting that it made him look "G." To me, "G" is the 7th letter of the alphabet, but for him it is apparently a particular look. I asked him what "G" meant and he said it was short for "gangsta." That prompted me to ask if he was aspiring to pursue a career in organized crime. He gave me the "you're an adult and you clearly do not understand" eye roll.
I am fairly certain that my appearance will never be "G" and that is frankly just fine with me. When I was a bit younger, I bucked the fashion trend of past generations by daring to wear my baseball cap backwards. In my youthful mind, this was somehow going to signal to the world that I was not to be trifled with. Nothing could have been further from the truth, but it didn't stop me from rotating that hat around on my head.
The next time you see a young person with a sticker on their hat or wearing pants that appear to be about a dozen sizes too big, don't try to understand. You aren't meant to get it.