Like DP3 said, no one likes a paycut...which is sarcastic, but kinda true.
Mack tried the Tour and, though injured around that time, didn't have much success.
As for Belmo, check out his interview with BJI a few issues back (he's on the cover). It should explain all. Basically, though, he makes plenty good money, is going to be engaged soon, lives in Australia (and would have to relocate so as to not incur ridiculous travel costs, etc.), and doesn't yet feel he could compete week-in, week-out at that level (in reality, I think what he means is, have a legit shot of winning each week, like a PDW, Walter, Norm, TJ, Barnes, etc...he doesn't want to be the second-tier PBA player like Oatman, Criss, et al).