Why create a law specifically for wheelies? Don't we already have laws against reckless driving? Seems like anything a biker does that puts themselves and other drivers at risk would be considered reckless.
I was driving my Yamaha 650 to class with my roommate on the back. The road in front of the dorm was a pretty steep hill with several speed bumps. I gave it a little too much gas on the downside of a speed bump, and the extra weight on the back caused me to accidentally pop a wheelie. I didn't realize it until I saw my roommates feet even with my waist! Good thing he had a backrest.

If a cop had been watching, a "wheelie ban" could have cost me a ticket I couldn't afford.
If the biker has no other traffic near them, all they are risking is their own safety. It's when they do these stunts in traffic that traffic cops need to intervene.
I'd prefer they have a ban on stunts. Otherwise they'll need to make a law for standing on the seat, sitting backwards on the handlebars, headstands,
intentional wheelies, etc.