So long as the price is the same for cash and card (and Pix?), then you should pick the one that gives you the best kickbacks. I don't think capping CC fees will actually lower prices for consumers much (because merchants prefer round prices for psychological pricing). For evidence, see the fairly uniform pricing of products sold in euros between countries, despite varying vat rates between eurozone countries.

> see the fairly uniform pricing of products sold in euros between countries, despite varying vat rates between eurozone countries.

Huh, not sure I agree with that (the uniform pricing thing). I mean, one should believe that, but it doesn't appear to be true. For example, recently I saw a tablet for 208 euro (converted from GBP) on amazon.co.uk, approx 220 euro from amazon.de and 360 euro from amazon.ie, for the same item.

I was really surprised because I figured electronics would be pretty similarly priced across the EU/UK, but apparently not.