> There is a reason why one can't pay off a credit card with another credit card.

Isn't that exactly what a credit card balance transfer is?

https://en.wikipedia.org/wiki/Credit_card_balance_transfer

in the corporate space this is super common and makes a lot of sense.. you sell debt at one rate, find a better rate deal that lets you pay it off later and trade one less favorable debt for the new better terms debt.

the company I work for has always done this very successfully.. is now a multi billion dollar multi national.