Some frames like the totem buttons still need to respond to clicks. The 9.0 API does allow toggling click and motion separately. The only argument I see against clearing the scripts is breaking any addon hooking them, but you do that turning off motion anyway. Either way, the hooks stop running. The benefit of clearing scripts is they allow many XML-defined functions to be garbage collected. These being Lua code enclosed in script tags instead of linked using the
function or
method attributes.
It may just be me, but I rather free unused memory than leave it tied up. I like having a tidy environment.