I don't know, but I can assume she was, since she asked the member of staff why she was eating and was told to "worry about yourself" and then went on Twitter to publicly complain about her to her employer, for eating lunch, rather than leave it at that.
Those aren't the actions of somebody who isn't bothered.
The phrase you used was "hot and bothered", obviously she took exception to the fact a staff member was eating it else she'd not have complained about it, that doesn't imply she'd got worked up as the phrase "hot and bothered" suggests and even if she had it doesn't imply that she's stupid as you asserted previously. You're just being silly yourself by assuming stupidity in someone who simply has different values or a different opinion to you.