That's my big argument against any of the "real" strap lock systems.
For me...I just find it kind a overkill to install those metal strap locks, and often having to fuck with the existing button, and they ain't cheap.
I mean, how many of us are twirling the guitars around our necks that we need that much strap lock!
Simple fix.
Take out the old strap button and wick some super glue into the screw hole. Screw the new button in and it wil stay. No problems ever.
My favorite "trick" for smaller screw holes that lose their tightness or even strip out...like for the strap button or even the screws on holding the back cover on an amp head or cab...is to grab a toothpick and break off a piece the depth of the hole and jam it in the hole, and it tightens right up again. You can even put a dab of wood glue on the toothpick, but then you want to wait for it to dry, because when wet, the screw will just disintegrate the toothpick in that wet state.
For slightly larger holes, I keep a few dowels in different sizes, and with a bigger hole I will always use some wood glue...just cut off a piece and jam it into the hole, and it's as good as new.
I've had only one strap button come lose...and I think it was actually because it was never tight to begin with, so the weight and movement of the guitar caused the screw to chew up the threads in the wood.