To be annoyed by play date

[Notthinkingclearly]

Ds (9) went to a tea last week with a boy from school.He had to ride in the car sitting on another childs lap as there was no room in car as the back was full of work gear. Then he watched a certificate 15 film while eating tea. He came home in in one piece and said he had a good time but I feel a bit annoyed. Would say anything or just not accept invite next time or am I reacting?

What movie was it? I'd get over that quicker than the car, I would be raging at that!! It might not stop me allowing him again but I would say "Will there be enough room in the car? Last there wasn't and to be honest I was annoyed over it, it really isn't worth risking it when we can reschedule for another day" or something similar

You're not overreacting. That's pretty poor. I don't think I would say anything but I would have my excuses ready for any future invitations.

YANBU.
You also need to teach your DS to say
'I'm not allowed in a car without a proper seat'
and
'I'm not allowed to watch any films above a PG rating' (or 12 if you must)

YANBU. The movie I wouldn't be happy about but would possibly think it was just a lapse in judgement. Sitting on someone's lap in the car however is illegal and I couldn't let it go. I would definitely be saying something about that.

I wouldn't send him again, they obviously have different standards to most people regarding safety and following the law. They won't change, just because you have a word with them.