It's unfortunate I know, but sometimes people just be jerks to be jerks. I've learned throughout my life that people sometimes find joy in hurting others, most of the time it has to do with their own insecurities and it's best not to take it to heart. Someone that has had a rough life or hasn't been treated good is most likely to do something like this, usually it gives them a sense of power or control which is something that they often lack if they do something like this. I know it can be hurtful but the best thing to do is to ignore it. Remember that a stranger will most likely say bad things to people they don't know because they don't know them and want to vent, it gives them a satisfaction of being able to try and push their own problems off on someone else. The best thing you can do is ignore things like this, after all a complete stranger who has never met you, barely knows you, and most likely will never come in contact with you in real life doesn't really have much to effect you with. They can say hurtful things, but the fact of the matter is they would just say this to anyone, they just single you out because you're there at the time. Otherwise they just think of you as an outlet for the time being, and really have no idea about who you are, or really care. Which again, because they are strangers, it shouldn't matter. I hope this helps you feel better.