I think that's a big part of it, particularly if you're trying for the procurement "loophole" which allows low to mid level employees to authorise spend of up to a certain level without going full a full blown procurement cycle.

A lot of the big firms (in the UK at least) will use Corporate AMEX charge cards (rather than credit cards) for this purpose. If they can't pay on their Corporate AMEX they'll often have to go through a more drawn out process to get the payment made by some other method unless they want to make it on a personal card and then claim it back.