After awhile, people started to berate him for this behavior. He apologized, but kept doing it. He kept getting answers, and kept learning.
Last I heard, he'd gone on to be a team lead, then run his own, successful company. He didn't let fear of public annoyance or seeming stupid hinder his own progress.
I'm not saying everyone should gleefully annoy others, but I've met far, far too many technical people who spend more time on their anxiety than they spend on actually learning and doing. You have to find a balance, and obsessing over the theoretical time expended across a group of people is probably not productive.