You know, I've never really needed strap locks on anything other than a Les Paul. The neck side strap will slip off if the strap hole is soft or old because your left shoulder tends to be outside of where the action is--unlike a J or P style bass.
Otherwise, it's just another piece of hardware to deal with:
A: The weight of the instrument is going to be at least a centimeter further away from its body. This puts more strain on the strap button and may cause it to wiggle loose prematurely.
B: Sometimes straplocked guitars won't fit in their cases if the straps are on. Of course I remember to take the strap off, but sometimes my buddy will try to help me out and spend a few minutes wondering why he can't shut the case.
Just something to think about if you are considering putting straplocks as a matter of course. I used to do that, but now I'll only do it if I'm really having a problem with nearly dropping a guitar.
EDIT: Sorry, sometimes I forget about exactly what the original poster was talking about. Yeah man, if the strap's coming off, try a strap that seems like it has a stiffer hole for the button. If you're too wild and crazy for that, maybe the locks are for you.