I must respectfully beg to differ. First, it may come with time rather than immediately, but such things often are the path to raises and promotions. Nothing in his original post would indicate it was not so at his company.

Now, if he really feels he has hit a ceiling at his company, that for whatever reason (politics, no room to move up, etc, etc) he really cannot get a raise or promotion there then he may want to think about leaving. But if he leaves just because most of his coworkers are 9-5 dayjob types then he is likely to be disappointed to find that it is the same in most other places.

If he really wants to be challenged by his coworkers and his environment is bothering him, then he needs to leave but he needs to look in very specific places to find that type of environment. He should look at start ups or research labs that are on the bleeding edge.

Otherwise, he should look to himself to find his own challenges and grow in his own ways, hopefully with a community outside of work to help him do that.