I hate my job sometimes

Okay, so I work at McDonald's; I have for about six months now. Not the best, but I simply can't find another job, and the pay is pretty good, so whateva. Anyway, some customers are simply so rude and weird. A guy asked me if we had buy one get one free mcdoubles, now we have never had that deal. I explained to him, pretty politely, that we don't have that deal and haven't previously. He makes me grab my manager, and she also explains that we don't have that deal. He walks away, and I think the interaction's over, but I find out later he wrote a bad review of me, calling me too intense and rude??? he was the one who was rude in the first place?? Anyway, moral of the story be nice to your food service workers, please :)