sometimes when you go to restaurants or stores, you see placards that read "bill must meet $25 limit for credit card use" or something.
but according to action line...
FIGHT THE POWER!There are no laws prohibiting such limits on purchases, but the practice violates the operating rules that merchants accepting Visa and MasterCard are required to follow.
A Visa official says the charge card rules in the merchant's agreement stipulate that no one should be required to make a minimum purchase. With millions of merchants accepting credit cards, the charge companies rely on consumers to be their eyes and ears, the official says.
You should file a complaint by calling the 800 number on the back of your card. A word from the issuing bank is usually all it takes to have merchants remove the limit.
Merchants who don't comply face the possibility of the charge card company rescinding its agreement with that merchant.