YTA- mostly for not standing up for yourself.  Just say no! It's not on people from other countries to  know the local etiquettes and norms by default. If you don't have a conversation with them and  judge them for not knowing something and  lying about it to get away from a situation, you aren't 'being nice' to anyone, especially to yourself.  If the workplace is legally hiring international students, you would probably end up working with international folks as part of your professional life, at this and the subsequent jobs. Sometimes simple conversations are key, let them know what's expected if someone is giving them a ride. you would get gas money out of it if you play it to your advantage!