The Minimum charges exist because it costs a company money to proccess a CC payment. If you don't purchase $X with you're CC, they are loosing money on the purchase.
Credit cards ar enot legal tender, so they can leaglly charge whatever minimum they want. The CC company agreements are the only things lmiting them...but don't cound on alot being done. Things are too good the way they are; the CC companies NEED a presence in bars, too moch money to be made. Bar owners NEED to be able to accept CC payments, or they'll loose buisness. But they need to keep making money:
Suppose a thousand people walk in and CC-buy a $5 pint each. The overhead on that pint is $3.50, so they make $1.50.....but, it costs $2 to proccess a cerdit card payment. So, those thousand beers cost the bar $500.
For the sake of civic economic responcebility, use cash at small buisness whenever possible, never use credit for less then $10. Fuck Wal Mart et al, they have better deals with CC companies and can afford the losses anyways.
So with respect to the minimum CC purchase, I have to side with the bars. Too many people come in for just a pint and a conversation, the small buisnesses can't take that hit. I'd counter this; What kind of a cunt doesn't have $6 cash on him to get a beer?
For this specific instance: The charge and Tip are outright theivery, plain and simple, the bitch needs fired and the bill needs voided. Also, as common as cards are, they NEED to tell you before they pour. No signs or that kind of bull shit; "good evening sir, cash or credit this evening?". Imagine filling up at a gas station that doens't take credit, but doesn't tell you until the gas is in your tank.