vary as a policy. I generally only fly bargain American airline Southwest, and they don't let you walk around. Seems like a pretty sensible regulation. And I can see letting people get up and walk around on long-haul flights. But long-haul is like trans-Atlantic, not 4 hrs.
Either way, a good flight attendant (even a bad one) could probably find a reason to talk to someone. Hell, all they'd have to do would be to have the pilot put the seatbelt light on, requiring everyone to sit back down.
But of course, no one could actually speak to the men, they could only jump to conclusions.