Rude thing you have experienced while eating dinner at a friend's house?

We went for dinner at one of the Professor's house a few months ago. Everyone from my lab was invited with their families. There were other people from collaborated labs too.

It was a huge gathering with plenty of food and people from almost all over the world.

The Prof's wife was the perfect host, talking to everyone and making sure that everyone was having a good time.

One of the guests was being a complete jerk. He would take a plate and fill it up with heaps of food, eat a bite or two and then just leave the plate wherever he was at that point and move to a different spot in the house and repeat this. He did it at least 3 times. When the party started to get over, everyone helped the hosts to clean up except him. He did nothing.

There was a lot of leftover food so the hosts asked everyone to feel free to take some home to which this jerk said “I didn't like the food much, so I don't want any but thanks anyway”.

I did not have the guts to look at the hosts' face. And no it was not a potluck or catered food, the couple had made everything themselves.

What he did that day was beyond rude. It was such a insensitive thing to say when he could have just shut his mouth up

Is this CORRECT way to speak about BAD FOOD? How would you react?