I have my bank send me an email saying "you've made a credit card purchase" every time I make a credit card purchase, just as a low-hassle way of keeping an eye on things, but those emails seem to be sent from completely separate systems from the (very occasional) marketing-ish email. The later they seem to contract out.

Certainly nothing that I need comes through email.

I would expect that they are separate systems for Citibank as well.