The bar doesn't pay the singers to sing. The singers pay the bar owner to be able to sing by paying for food and drinks of some kind.
No food and drinks paid for, no singers, no karaoke, no bar.
Singers are unpaid entertainment. I need paid to provide the vehicle for the singers to sing. Each singer doesn't bring along their own PA system and music and microphones. Like paid performers.
The reason people go to a karaoke night at a bar is to sing. They wouldn't be there if the bar owner wasn't willing to pay for the KJ to be there so his customers can sing. His intention is to make money in the process. Because he operates a for profit business. Not a charity or a food bank. He only has a limited means of making that money. Selling prepared food and drinks.
If you go grocery shopping, do you eat & drink everything you can before you get to the check out with an empty cart? Ohhhh...I'm not buying anything today. Just browsing. Oh and by the way..the chips were stale and the Musak songs were too slow and boring, the meat smells funny, there was no free water, the rest rooms are dirty and I'll be back to do it all again the same time next week. Can you have everything corrected by then? I'm your best customer.
You have to pay for the garbage men to take away you garbage. If I don't want to pay them and I put my garbage in your cans...That's called Theft of Services. It's a crime. If you are entertained all night without paying for anything you are stealing from the bar owner. You took advantage of the musical service he paid for. His electric and water and sewer, his help and his entertainment.
Now there was no cover charge but it doesn't mean that everything is free to all without any type of an expected donation in the form of purchasing something. To partake of his generous hospitality for free is wrong. It's just plain rude. You wouldn't want a hundred strange people coming to your house night after night to watch your pay-per-view and drink for free while you wait on them hand and foot.
I don't see how the free water drinkers think their actions are exceptable and should be tolerated. That takes a lot of nerve.
Next time someone complains about something you didn't do right or should have done different...like the KJ shouldn't be singing or when am I up and how come they sang before me...see if it's a water drinker doing the loudest yelling...
. is CHEAP. 
Because you had to pay for a water.
