For the majority of merchants, who comply with it, the no-surcharge rule means that consumers do not normally get a lower price if they are willing to pay cash, or use a lower-cost payment system, such as bank debit cards, which usually have a flat fee rather than a percentage fee. Therefore the rule tilts the market for payment systems in favour of credit and charge cards, and give the card systems a greater share of consumer purchases than would otherwise be the case. The processing cost of a cash payment for the retailer is no more than the cost of taking it securely to the bank, and they get instantly available funds rather than having to wait for the bank or charge-card companies to credit their account a few days later.
Retailers have to make their profit somewhere, so if they make less profit from card purchases, they have to make more profit from cash and debit-card purchases. As a result, sticker prices are higher than they would otherwise be.
The no-surcharge rule also reduces competition for the level of interchange fees, because consumers don't get a lower price if they use a different card network, whereas the card-issuing banks will sign up with the payment network which offers them the highest interchange fee. So payment networks compete to pay the banks the highest fees, driving up the merchant discounts charged to retailers. Only in the extreme will you find that some retailers simply refuse to sign up with payment networks (in particular, American Express) because of the high merchant discount. However, most retailers cannot afford to ignore the two major credit card networks Visa and MasterCard, as there will always be people who want to buy on credit.