Hehe.. i think the ones the lasers come with arent rated for the current they have to switch either. This type of switch is really built to be a control button like on a cd player, not to really switch main power by itself.
Then again, if its actually rated for 100 mA or so, chances are it will live as a power switch in these lasers, just not as long as under normal load.
The ones I see are rated 50mA@12v.. now at 3v, I bet that is higher, but I doubt the 400 or so mA(AS far as I know anyhow) that the higher power greens draw. :-/
Nah, current rating hardly depends on the voltage. The rating just means it is guaranteed to survive 50 mA and not to spark over at 12V, and under those conditions meet its stated lifetime (could be 100.000 presses, depends).
Driving these things at nearly 10x rated power obviously compomises their lifetime, but i dont think it'll fuse shut at the first attempt or something.