Once the transaction goes through (i.e. not preemptively blocked), you are at the mercy of the bank. Most of the time it works, but I have friends' stories of losing several thousand dollars on a chequing account due to fraud and being unable to convince their bank that they deserve their money back.

That's assuming that you notice the fraudulent transaction, meaning you have to monitor your account regularly and carefully look at each transaction to verify it's legitimate.

That's a decent amount of extra work.

Its a decent amount of work if you are upper middle class. If you are scraping by with less than $400 for emergencies like 40% of America, losing $25 is probably a flashing red light.

In my experience, people who are "scraping by" usually have to work a lot more than we do, sometimes at two or more separate jobs. That's even less time to sit around and review credit card bills line by line.