Because US banks prefer to keep customers happy, unlike EU banks.

How does that work? If you can be sure it was owner initiated, then you allow, outside of some corner cases (which work here too), people to fraud merchants. That makes people happy?

Edit; I know there are more reasons for chargeback and those you can get across the line here too, however, 'frivolous' chargebacks are not good for anyone but they are easy in the US.

You are assuming that people only do chargeback in the case of some kind of fraud where other people stole your card details and spent your money. That is not the case. There are many other reasons to do a chargeback, far more reasons in fact.

AFAIK there it was put in the law(at least US/Canada) that credit card company have to return money and deal with fraudsters their way, CC companies have some really rabid investigators. If they behave improperly you can voice a complaint for financial regulatory authorities - banks really hate dealing with the government.

Yeah, the law is on your (customer's) side in the EU also. Unfortunately people don't know that, so banks can afford to bully their customers into renouncing their claims. Technically if you are the type of person who knows how to deal with these types of problematic businesses that push you around, you will eventually prevail, but it will cost you a lot of time and effort. In my case, the financial loss was not high enough in order to waste even more than three trips to the bank.

My partner's parents were hit hard though, about €5k. They argued back and forth with the bank for about 6 months to no avail. "Sorry, we can't do anything" type of answers. The bank also tried to trick them into signing "fraud forms" that in the fine print absolved the bank of any responsibility. It was only after I actually filed a claim with relevant financial authorities, and then hit the bank with that that they suddenly got their money back.

The interesting thing is that this mentality is so prevalent that even the non-fraud department bank employees genuinely didn't know that the bank is supposed to actually help them. Many of them told us their own stories about how they were defrauded (I have no reason to suspect they were lying because they were family friends, and I heard the stories before our incident).