I feel like Supreme's more popular in the bigger cities like NY and LA, etc. but when it comes down to the suburbs, (at least where I'm from) you mostly get the Zumiez kids rocking The Hundreds, Obey, Diamond, etc. Check your Craigslist listings for "Supreme" in cities all over the US. The ones with the most listings are NYC, LA (and neighboring cities), SF, and Phoenix. Other than that, a lot of areas don't even have listings under "Supreme".
I know mosta you downvote whenever someone posts "I'm the only person who wear's Supreme where I'm from," but honestly, I feel like it's kinda true. At most, I've seen about 5 different people around my city who wear Supreme. I know there are definitely more by the member-count in the local FB groups I'm in, but Supreme's definitely not one of the more "known" brands in my area.
Don't mean to go too far into it, just felt like saying since it happened to be the topic at hand..