> Why is that controversial?

I don't know if it's controversial, but I think for most people, keeping up with your current card statement isn't something you do daily. Sometimes companies have a way to notify you of new charges immediately, sometimes not. Being surprised at the end of the month is more common than you'd think.

How would you know unless you check your credit card statement every day?

FWIW, some banks will let you setup email alerts for when your cc is used, or used over a certain threshold.

I have mine setup to send me a text message for every transaction. However, I suppose I might stop getting the texts if my number was compromised.

Putting the "15" in italics isn't doing yourself any favors when asking aita

I for one don't really look at any banking stuff these days. I just live well within my means. If you have a generally healthy financial situation there is no need to constantly check.

He noticed the first time he got a bill at the end of the month, it doesn't seem that difficult to understand.