Bar tip money also the grooms?

A few years ago I was in a wedding. The next morning was present opening and the groom was counting out the tip jar from the bar. He then gave half to the bartender and kept the other half. He said it was the agreement.

The wedding was at a the brides parents farm. The bartender was a friend of the groom. The liquor was purchased by the bride and groom but they charged everyone for it. I believe each beer was $2 wine was $4 and soda was $1.

I was in shock I just stood there. They already made money from their selling of the liquor and now they were taking tip. There was no sign saying the tip money was for the bride and groom. So people assumed this guy was working this wedding for tip money.

In my mind it was a money grab and I was appalled. How would you have handled this?

At our wedding we paid for the wine, beer, and soda. We felt that was the right gesture of gratitude for our friends and family.

Explanation of bartender: "friend of the groom" is very vague they met once 3 years prior they had a mutual friend in common. Sorry for my bad explanation.