Frankly, I would not have paid whether I had the cash or not.
When we are hit for a charitable donation after a hosted dinner, we don't contribute, so I wouldn't do it here. Some might not see that as relevant, but it is to us. Please don't hijack the thread with that small point.
I agree, the Chef probably made out like a bandit.
At one wedding reception we went to, the bartender put out a tip jar. As we were paying the bar bill, we told her to put it away. We tipped her well at the end, which was our responsibility. I think pop and beer were free, the guests paid for mixed drinks. We tipped for the whole bill.