The way it is...

B2B merchants pay higher payment processing fees because most of their transactions are done on corporate credit cards.

Bankcard (credit, rewards, check, corporate, government, debit) transaction usually fall into one of three possible certification levels, they are:

1. Qualified - Consumer card present at point of sale. The merchant pays about 1.7% of the sales amount for this type of transaction.
2. Mid-Qualified - Consumer card NOT present at the point of sale. These are transactions done on the phone or Internet and the merchant pays about 2.7% of the sales amount for this type of transaction.
3. Non-Qualified - Corporate or Government card. The merchant pays about 3.5% of the sales amount to process these payments.