There is. Citi bought the account balances from American Express and paid a billion dollar premium. There wouldn't be a premium if there were no finance charge revenue stream.
Wouldn’t there still have been a premium to pay so that Amex wouldn’t be able to still keep the card members on a card type which it would no longer be able to offer but may have otherwise been able to retain?
Finance charge revenue streams are of course a factor in how much of a premium an asset acquirer may or may not want to pay to buy a portfolio.