Credit card fees and trade

I started shopping at a small neighborhood veggie store. I had been regularly spending about $20 a week for two months, always on my credit card as I do with all purchases. Finally the day came when my total purchases were under $10 and the owner pointed to the sign that says 'no credit card purchases under $10'.  I left my purchases on the counter and said 'thank you.'  This happens once a decade.

I used to think to myself 'how can a business turn away a $1,000 a year customer for a fraction of a dollar (3% credit card charge on of $9.99)'? 

Now it is a reminder of one of my contributions to human understanding of commerce.  There are three kinds of commerce, each with a different motivation.  There is trade, industry and clientry.  This veggie store is built on trade, the oldest form of commerce.  The object of trade is to made sufficient profit on EACH transaction to replace the merchandise and cover overhead.  This (Chinese) woman can never see me as a repeating customer or she would be rejecting her 2,000 year old finely honed cultural skills as a trader.

Industry is motivated by lowering costs, clientry is motivate by a desired lifetime relationship with the customer.  Both industry and clientry would see me as a desirable repeating customer.

Only in a trade business would there be a minimum fee.

As I've started saying: ' Thats reality, folks....a trader' 

Of course the veggie store owner signed a credit card contract not to have a minimum and someone will take the time to report her.