to Machination:
Well, they are sort of permanent-- Bonded on, not intended to be removed at all. If they chip or fail, the patient would have to get them re-done..
They have their uses though... For example, some diastemas can be closed by using veneers, for people who have that "gat-toothed" look but don't like it.
to Critterbug:
Yep, some schools give their students a large discount, some do it for free. While I don't need veneers, I'm still milking my dental school for everything else I need though, like having my 3rd molars taken out, sealants, fillings, and 6-month recalls. 😀