Doesn't using ACH imply giving a company direct access to your bank account? Credit cards offer all sorts of consumer protections that ACH doesn't have, e.g., the customer can be immediately reimbursed for fraudulent transactions, etc.
Not to mention that credit cards allow people to buy stuff they can't really afford on credit. If you remove that ability, you'll be losing a lot of potential customers.
Not to mention that credit cards allow people to buy stuff they can't really afford on credit. If you remove that ability, you'll be losing a lot of potential customers.