The problem is that a low level employee doesn't have the money to fight something like this. The simple fact that they can be litigated is enough.

Would a company spend money to enforce it? With non poaches, worst thing i've seen was a threatening note from a lawyer. No one wants to spend the money to take it court.

Usually my answer is no. I sign them and then, personally, complete disregard them because I think it's highly unlikely a company would enforce it on a low level employee like myself. The fact that they could try is usually enough to scare smaller employers away from even trying though.

Most sentiment seems to be that they "would never hold up in court". Every once now and then a case does come up though http://arstechnica.com/tech-policy/2014/07/amazon-sues-ex-em...

I know at least one corporate attorney that says flipping burgers would be a breach of your non-compete as far as he's concerned, i.e. "we reserve the right to intimidate you"