Is there any benefit to trying to purchase in store, like at a AT&T or T-Mobile store? I did a quick lookup of the MCC for Visa, and the T-Mobile ones at least are listed as "PHONE SERVICES & EQUIPMENT - 4812", so my guess is it wouldn't qualify?
Does this also mean that any refill cards bought in store to top up a prepaid plan won't qualify for the 5x bonus too?