Is it alright for my family to be offended by this?

So for thanks giving, we had a Reunion at my sister in laws house in bal harbor (part of miami). They are very well off. My husband's other sister family who is also very well off was invited to stay at their house the whole week. My family (3 children and my husband) and several other families were just told to stay at a hotel. We aren't rich so i think that they might be looking down on us and taking advantage of us. My sisters in law are both very arrogant. My sister in law who hosted the Reunion said it was because her daughter (15) and her sisters kids (13 year old girl and 12 year old boy) get along well. I have a 15 year old daughter so i don't under stand this at all. What do you think.