I remember, way back when, when you could just show up and try and go standby earlier/later in the same day (especially later!). My thought is this: they have nothing to lose by putting you on an earlier flight (frees up seats later). If you try and standby for a later flight and there is no room, then you're out of luck. I always knew that in the back of my head and thought it was a fair compromise (got badly burned once, but c'est la vie).

I'm even willing to pay the $25, but they need to extend that to later flights as well, IMO.