Casting my vote for rude, childish, passive/aggressive, and mean-spirited. This is a bully who never grew up.
I'd also be having harsh words with the husband.
And if this happens again, don't cry; get angry. Your BIL was looking to make you cry. I might have tossed them all out but not before telling him in the coldest possible tone of voice that he ruined something I spent significant time, effort, and money for the enjoyment of others. I'd also use the children as the coup de grace on that statement.