Except where the part where they escape and you can't find them and they die. Plus people could accidentally step on them. And they're really expensive. If you were determined to have a BEL at your wedding (which would be a lot of very unhealthy stress on the snakes) I think you would be better off confining it to staying around your neck or just leave it at home. I would never want to have a wedding where there would be loose snakes just because I love snakes. It's irresponsible and dangerous.

Though you could possibly rent your snake to be in wedding pictures though I think anybody that would want a snake in their wedding pictures would own one of their own that they would want with them.

(I really, really hope you're joking and I'm just overreacting because if you're serious...)