...unless you were doing uber coins (current back order era notwithstanding) on every one of your cards and/or maxing them out (and continually paying them off in a well-managed way) via some other miles earning gigs so you could earn on every card/airline/hotel as much as possible.... I mean, just think if you could nearly max out every card you have with coins every 10 days, then pay it off and do it again?

That said, I will tell you I have a significant handful of cards and I do use them for different things. I rotate my every day ones and I assign others to things like, for example, the following:

My Hilton Amex auto-pays the cable and phone bill and I use it to do most of the groceries and pharma shopping because it earns 6 points/dollar (I think it still does, that is lol)

If I happen to find myself in need of a rental car, or if I am going to ever pay for a hotel or airline ticket or parking, I could use the capital one because these travel expenses could be redeemed with points earned on those cards. I could get reimbursed for such expenses if it's a work thing, AND pay for all of it on my bill with C1 miles that I earned along the way.

My new 5% card is also in my wallet for many every day purchases as well as big ones that, when I add it all up, could amount to well over $30k a month. This card is new for me so I gotta keep it going like that to see what comes of it.

We also must not forget about the SPG Amex and a host of other cards that, beyond sign up bonus and spend requirements, can continue to earn many points if used continually where well planned out and needed.

MM