Grips wear out... Just have two holes on the lever which can be used for drilling pilot holes and then screw in 2 screws.
Just take some clamps used for woodworking and slap those on. Some of those come with racketing mechanisms and can hold for very long periods of time (often necessary, since sometimes people clamp wood into place for months at a time).
I'd think the grips would wear out due to friction which should be minimal in what I'm thinking. Something that is a no tool install would sell much better.