i totally disagree with making any comments about anybody based on anything other than there actual behaviour so appearance is out (unless ofcourse you are making a compliment) but i do have personal experance of a lady accusing me of laughing at her and it was extreamly distressing to me.
over 25 years ago at about 17yo i was on a train in a station sat at one of the seats with a table a rather fit bloke was sat oppersit me and had been for awhile and we were chatting just genral chit chat but very much of the flirting type anyway he told me a joke a very basic none offensive rather childish one about foot prints in butter, and i laughed.
he then asked if i wanted a coffee and i said whilst pointing the cafe is all the way over there so you probally dont hjave enough time to grab one why dont we wait till the cart comes round.
next thing i know a lady is stood infront of me screaming abuse at me she actually called me a cunt then started yelling stuff about being large not being her fault it was medical.
i was so embarrised i couldnt even say that i hadnt even seen her let alone laughed at her and then had to spend another 3 hours on a train with other people thinking i must have done something it was quite possibly one of the most humiliating experances of my life.
as a result if i even notice a larger person i am so worrid about anything i say or do being mistaken that i tend to go quiet, i wish i could just stop doing it but for some reason i cant,before that happened i wouldnt have even noticed if a person was or not.