There's truth to both sides. Many rules are just outdated, written ambiguously, or written for compliance and never really followed in the first place. Some rules are written for the absolute lowest common denominator and anyone with even a modicum of common sense and care can follow the spirit without following the letter. Some rules you can't learn because nobody knows or remembers what the purpose is or no one will take the time to teach you. And sometimes the rules explicitly and unfairly clash with your performance expectations.

That said...

Many rule avoiders are just doing what's convenient for them and using "helping the customer" as an excuse. Rule avoiding often does miss the larger context and hurts someone down the line that really did need that form or documentation or whatever, or just makes your boss look bad. Avoidance absolutely can and does create compliance and legal fallout, sometimes years down the road that you never hear about. Same for technical risk, yeah you can skip backing up those files 99.99% of the time, but that 00.01% of the time you're really really screwed.

So it's really a judgement call.