If you have enough cash customers, total card transaction costs are not 3-5% of revenue. If you don’t, you’re definitely putting 3-5% back into your pricing to cover the fees.
Ultimately, my point is (not even addressing the legality of Visa's compulsory pricing attempts) the cost of upfront analysis to set pricing appropriately is easily dwarfed by the cost of labor and throughput when adjusting the price by employees at the point of sale. Maybe the merchants adjusting at sale are getting a benefit in the form of customer awareness, but I have doubts.