i went to the mall to do stuff and wanted to try on some sweaters and asked the clerk where the fitting rooms were. and this dude instantly had this quite severe sort of - disappointed stern adult look about him as he pointed me there. like, he was very sort of clean and clean shaven and had a fitted sweater and everything. and i had a hat and a beard and longish hair and i'm a young guy so like yeah i guess but still i mean dude - you work at the macy's, wtf am i supposed to be wearing to shop at a store and speak to you?
I'd like to suggest a different reason for the likely judgement: You didn't see the obvious (in his view) sign for the fitting rooms.
Neither of you has to be 100% wrong in the situation. Just because he spends up 40 hours a week seeing that sign and 100% thinks it is GLARINGLY obvious doesn't mean you 100% didn't even try looking for the sign and possibly distracted him from a (perceived) important task to make up for your laziness.
It's a balance. You can both be 50% objectively correct or any variation of levels. The sign could have been higher or lower or a different look than you were used to AND you only glanced around and didn't really stop to look.
I know for a fact that I've been on both sides of this kind of scenario. Would bet most could find one of each in their lives, too. So it's a learning experience, remember that what is obvious/simple for one person (you/someone else) isn't obvious to another person (someone else/you) and try to act accordingly.
But the fart comment is very insightful, you know?
In many stores around me the fitting rooms are locked and require keys for entry due to theft. I'm not sure that was it. I'm wondering if OP is overthinking the situation and the guy just remembered something semi-traumatic from earlier in the day, or saw something bad happening behind OP or something.