> “Also, credit card fees are not 4%, they're 1.5-3.5% with an average of around 2.3%.”

And they’re much lower than that in the UK and EU. Even the smallest UK retailers can pay as low as 1.6% or 0.8% + £0.02. The big guys who are running billions of £ are paying 0.5% or less.

(These apply to in-person transactions, accepting cards on the internet typically costs more).