Who the hell uses a Credit Card to buy a computer? It's not like a computer is a major expense.
Of course walking into the Apple Store and buying three iMacs with cash causes confusion. They need to bring in two witnesses to watch the cash being counted.
I love the guys at the Apple Store in Christiana Mall ( Delaware ) they always greet me with a smile and their hands held open ( to take my money ).
I got there because there is no sales tax, and when you buy three or more Apple computers at once that 6% adds up.
I always love that response. Who buys a computer with a credit card? Those who want an additional 4% cash back (my case), or those who want 3,500 airline miles (some others motivation)... Just because you chose to use a form of payment which hasn't been mainstream since the 1950's, don't act like buying on a credit card is so strange.
Buying on a credit card gives you an extra level of protection in the event of a purchase dispute, warranty issue, return period extension, not to mention the loyalty points or cash back. You completely contradict yourself when you talk about how quickly 6% off adds up, yet fail to see how 10% off would add up even more.
Just because you may not be responsible enough to buy it on a credit card, then give your "cash" to the credit card company, don't discredit the method as some foreign way to buy.