Judging by my own days as a teenager buying alcohol with a fake I.D. :
Most places card reasonably well and can't be fooled. The ones that don't become well-known among teens and that's where the underage kids go. I'm reckoning that 98% of the places that ID passed didn't card at all.
When carding a lot of places were just looking for a reaction, not an ID. Most kids without an ID or a bad fake would fumble around at that point, pretend to be looking for the ID, mumble something about losing it, and leave. If a person confidently produced a laminated card of the right size and shape the person checking would not even glance at it. Just the act of producing it without fear was often enough to convince the checker that it was legit. That accounts for the other 2%.
There were times I had a pretty decent fake and times when I had a truly laughable fake that was barely one step above having a cartoon of Bobby Hill. The bad fakes worked about as often as the good ones did.