Ask your legal department about that. Sure, engineers don't care about licensing at all, but we are not the only players here.

Are legal departments in the habit of reviewing all code line by line? Seems like that would be cost prohibitive...

Obviously they aren't, but just as obviously, "the legal department didn't review this, therefore it's safe to assume it's legal" would not pass muster with said legal department. :) Kiro's comment ("if someone gets access to their code and sees all the violations they're screwed anyway") is probably technically accurate, even if in practice you're unlikely to get caught. As other people have noted elsewhere in the comments here, the Google v. Oracle case over Java definitely suggests that verbatim copying of just a few lines, even for trivial functions, is enough to get you in trouble if those lines aren't licensed in a way that lets you do that.

No legal come up to you and say stuff like:

"You guys aren't using any free software are you? Because you can't do that."

"You mean copying software source code without respecting the license, right? Because we absolutely respect all licenses fully."

"No I mean you can't use Free software! It's a clear management directive! What are you doing?!?"

"Is that an apple laptop you're using there? Ever had a look at the software licenses for it?"

Legal are generally idiotically ignorant about the real issues. Whose fault that is we can argue about.

This is absolutely not true. While some individuals might not care and might not always conform to their companies' policies, most companies have policies, and most employees are aware of and mindful of these policies.

It's absolutely the case that before using certain libraries, most engineers in large corporations will make sure they are allowed to use that library. And if they don't, they are doing their job very badly IMO.

This kind of sucks honestly, copy and pasting without understanding has lead to all sorts of issues in IT. Not to mention legal issues as mentioned by another reply.