In DC BesBuy must be paid in person, such as with a CC, DC, or cash.
About 2yrs ago Spring wouldn't let me charge to their account a phone purchase. I was surprised, but they said it was a new policy. At the time, I had 3 lines on my account, always paid in full and on time, and had no limit on my account. They said that it had nothing to do with my account.
I actually prefer paying with my CC. AMEX doubles warranties and if you lose the device or it breaks within 90 days they replace the device for the price you paid!