The reason the units required is going up is that the price per unit is going down. When I bought my Sam's Card a year ago the price per minute was 5.9 cents it is now much lower. AT&T has to pay the owner of the payphone 50 cents for your use of the payphone. Even with this high charge the profitability of pay phones is decreasing and some people say the pay phone is becoming extinct due to cell phones. I don't have a cell phone, and hopefully won't ever.

Secondly, You can have a friend buy the card for you at Sam's and then anyone can renew a card with a credit card. The best news is you can re-charge your AT&T card with Diner's!!