I don’t know if it should bother you, but it would bother me. Different families have different traditions and expectations, but I would want my kid in the condo with me, and parents/in-laws at a hotel. Airbeds only go so far, I need privacy, not just a place to sleep.
Worth bringing up to your DH and DS, maybe they have some ideas. Does your DH have siblings, or is your MIL yours alone for holidays?