[randallsquared]

I don't eat by myself nearly every day because I dislike my co-workers -- I actually do like my co-workers, and my job would be a nightmare if I didn't. That doesn't mean that, come lunchtime, I won't nearly always take the opportunity to be by myself (conceptually, even though I'm still surrounded by people).

On your assertion that Joel is an introvert:

[...] but you'll also see a distressing number of loners eating by themselves.

Distressing? Really? I don't think an introvert would say that, and his later assertion that

Being in any clique, even if it's just the nerds, is vastly preferable than eating alone.

, and the "obligated to pretend" language, seems to indicate that he's an extrovert. I'm not sure if he's claimed to be an introvert, but if so, it's a pretty weird juxtaposition.