If you happen to live in potentially extreme environments, it would pay to pay attention to the Codes. Yes, corners are 'cut' all the time. I happen to have a conscience. If it's my house, well, if I'm gonna be 'lax', then I have to live in the bed I make. But if it's someone else's house, I wouldn't be able to sleep at nigh if being 'lax' meant making a few extra $$$ at someone else's expense.
About saving time - Who doesn't want that? You can pay now or pay later in your 'time' if it happens that a wall falls because you didn't toe-nail it when you should have (per code). Or you didn't cross-brace when you should have. And so on.
Well, I just fell off my soap box. If you can, let me know the houses you work on so I can stay away from them.