Mostly because every single transaction would be annoying and I would end up ignoring the notifications. I have >$100 notifications on some cards, but forgot to

Mostly because every single transaction would be annoying and I would end up ignoring the notifications. I have >$100 notifications on some cards, but forgot to add them to others. And honestly it happens so rarely, I review my statements often, and the bank reimburses me without issue when it does. So I don't really worry about it.