Also defending and waiting always easier and cheaper, then pushing.
Yes, and smarter too sometimes, even as allies, although most often you get to hear the mantra "allies push, axis dig in" on repeat. It can be better even as allies to camp at some point rather than to overextend and have to run all the way home again (especially on big maps). I think staying power is important. Not the whole game, when one notices heavy arty incoming then it's time to start moving again and hopfully you'll have troops to scout for your Jacksons and such.
I do agree that allies should be more eager to push early game though.