The root of this evil is the deal the card companies made with the EU some 10 years ago: A cap on the interchange fees in exchange for the ban on card surcharges.

If the card processing fees could be added to the customer's bill, it would be in the customer's interest to support a cheaper/free alternative. But since card payments are "free" in the eye of the consumer, why should he be using anything but the most convenient option? And what is more convenient than just touching your card/phone to the terminal? As long as this deal stands, EU merchants will be slaves to the card companies.