Wall Street non-competes are only enforced if they pay you your base salary during the period. They can also opt to not do that and waive the non-compete, in which case you can work anywhere. I think it's ridiculous that Subway has non-competes, but with regards to the article I doubt anyone is forced to choose between working for a trading firm and starving. There also are some firms that do not do non-competes. So it's closer to voluntary than involuntary I'd say, though very few decisions are truly 100% personal choice.