Bains looked like complete ass even in the preseason though. People keep going to bat for him, but he looks terribly out of his depth at the NHL level. Not a guy i'd dare throw into a playoff game for example.
Podkolzin...maybe. Karlsson has also been a bizarre callup. He does absolutely nothing.
Ultimately, looking good at the AHL level isn't always a real telling forecaster of how they'll do at the NHL level. Whereas Studnicka...well, we know what he can do there. It's not much...but it's also not going to hurt you. There's value in having extra rungs of that sort of depth available, stashed away in the AHL.
The only way it makes sense to just give away that sort of stashed depth, is if that pick ends up being used to help bolster the roster with more quality NHL level depth at some point. As well as just doing a solid for a player like Studnicka, which also makes agents happy (building a little credit there, greasing the wheels for future trades, etc.).
Giving away playable NHL depth that you've stashed in the NHL, just because you think someone like Bains "deserves" a callup is just malpractice. That's just removing rungs from your depth for no reason. Nothing was stopping them from calling up Bains over Studnicka anyway. That's just removing options. Unless...like i said, this ends up being the sort of move that helps set up a future move to bring in a depth guy who is much better than either of Studnicka or Bains.