I have name changed for this as I don't want friends to recognise me and it's my first post in AIBU and I'm a wimp. 
About six months ago, we had about 10 friends round for dinner. One couple had a toddler. I was in the kitchen serving up and returned to the dining table in the living room with the food. The parents of the toddler were changing their nappy at the other end of the room and I must admit I blanched - there was poo everywhere and it stunk. The smell lasted through the first course and when they left, my DH and I both said how rude it was.
Last week we had a different set of friends round for a meal on boxing day and again, one set of parents had a toddler. When we finished our meal, the toddler announced he'd done a poo. The parents started changing the child on our carpet with no changing mat and leaving the rolled dirty nappy on our floor.
As this has happened with two different sets of parents, are we the uptight ones or is this gross? We have a perfectly functional bathroom.
(I promise I'm not the poo troll)