[mattmaroon]

Everyone should have at least 3. If you aren't fully taking advantage of credit card rewards you are subsidizing people like me who do.

[aestra]

"Everyone" is a far stretch. More like "people who like to (or don't mind) managing their finances at a finer level and also don't spend above their means."

Which is maybe 35% of the American population.

Some people are just fine not bothering with credit cards because convenience/simplicity/ease is more important to them. It's all about individual preferences and priority.