Certain states actually do require permits... Florida is very strict, requiring permits and microchips, and apparently requires you to be able to jump through hoops of fire, as well. Tom Crutchfield is always talking about it.
I microchipped both of my Burms, just to be that "good keeper," considering all the pressure they are having lately, and I live in NJ. It may be unnecessary, but little things like that could mean the difference of what eyes are on me and what eyes aren't when more laws start coming down in our area. I also microchipped 2 of my adult female ball pythons: my Albino Female being one of them, since she is on a breeding loan with a friend, just in case.
If law required it, I'm with you SYF, I would have no problem putting in the extra cash to microchip all of my snakes. It would be really hard to regulate however, since you really shouldn't (and physically can't) microchip smaller snakes and baby snakes before they're a certain size. Considering a lot of snake sales happen when they're hatchlings, I would imagine the only thing you could do is to have to be fines and stuff for getting caught having a snake that wasn't microchipped by a certain age, etc.
But Donnie is right, legislation hates compromise.