I never heard of anyone disputing his Visa / MasterCard payment in my country.

That's probably because people pay online only at a very limited number of places they trust, and it's easier to solve issues with the local merchants directly.

Another reason might be, that many online payments are made via direct bank tranfers / SEPA, which can be both, fee-free and instant, across the entire EU.

Essentially, everything is based on trust. Nobody puts his debit / credit card details into a form of a website he never heard before, and nobody risks his business reputation if he has managed to earn it.

It's pretty short sighted to think you can trust your "debit" card number with any online merchant nowadays. I wouldn't shop online, or even at physical stores for that matter without the safety net a credit card provides. I don't mind paying the extra bit on top for this protection (which is negligible due to rewards).

I definitely wouldn't use a debit card if I lived in the US, just because of the general atmosphere of "suing and disputing" everyone and everything, if something goes wrong. But debit cards work just fine in the EU, where governments take proactive steps to protect consumer rights, and an average consumer is rarely expected to fight for himself. I have personally never had to.

I can dispute a charge on my debit card just as I can dispute it on my credit card. Disputes get harder for payments made using my pin, but any charge from an internet payment is trivial. I can also dispute any SEPA-withdrawal. The best option for a merchant is pre-payment via SEPA transfer initiated from my side. That’s pretty hard to dispute.

You can dispute, but the big difference between credit card and debit card is that on credit card, each transaction is insured through the merchant fee. Mastercard and Visa's rules also specific require the card lender to repay a disputed charge in full, regardless if they can manage to reverse a transaction or not; the same is not the case for debit cards (even if they are branded with the Mastercard/Visa logo).

what??

what makes you think debit cards are less safe than credit cards? as far as I know here in EU all debit cards are smart cards with PIN code protection, what exactly is the unsafe part?

are you confusing debit cards with magstripe cards?

I know that with credit cards money lost is the credit card's company, and there's a fair number of protections to keep consumers from paying that bill in the case of fraud, but with a debit card money lost would be directly from a bank account, and there seems to be less. Is there more fraud protection for bank cards in the EU?

In France, for all banks I know, you can call, say "starting this date, all activity on my card is fraud", and you are refunded, no questions asked in the vast majority of cases. This seems quite enough for me.

Ah, so you do have those sorts of protections.

In my country, it's possible to get the money back if somebody charged your debit card without your knowledge, but not if you approved the payment yourself. In such case, you are expected to solve the issue with the merchant yourself. Just as you would be, if you had paid in cash. Which seems to be reasonable considering that the maximum allowed debit card fee in the EU is 0.2%.