I don't think too many pilot groups are going to line up to tell their employers "We're not taking on bigger jets." You couldn't really do that even if you wanted to. You can't just go on strike because you don't like the way your company is growing. Regionals fly what they fly based on the scope of their mainline partners, not the other way around. I wish everyday the 170/175/700/900 were on mainline property. But they're not...and it's not because RAH/Comair/ASA/SkyWest/PSA/Eagle/anyone else said "Man, I'd really like to stay at a regional longer and fly some bigger jets."