Reasons for just calling with A7? We think we're ahead most of the time so why just call with a hand that never improves on turn/river? We aren't happy to get it in here I suppose, so is click/fold better than call/hope?
Understand all the others being calls tho.
I like the idea Tal, A7 doesn't play that well HOWEVER it does have one piece of merit and that it that it plays better against the NFD than some of the others.
Also....
And yes, I would crammmmm every single hand I cr if he 3bts flop. He's repping 77/55 and gl sir.
If this is actually true, not sure it really is seems way better to just have a calling range OTF than none, but that would make

a call, A7 (meh) fold, and all the others very very easy 3bet/calls.
This would be why I think not having a flatting or a folding range is a bad idea.