Hmmm I never had anyone ask if I was paying cash or room card, they ask if we are on a dining plan. And for the meals, all you would have had to do was noticed the error before you left, and had them removed. Where they dont charge your 'real' credit card, there would have been no wrong charges ever show up on your credit card.
Also, as someone else stated, you can also put cash on your KTTW card. Now, some folks that work the check in desks dont like to deal with cash if possible, or just dont want to take the time to apply it, but it can be done. I tried to do it at CSR and was told it couldnt be done. So here I am walking around with about a grand for all our stuff for the week, and daily I'd go and pay off the KTTW card, one of the managers saw my cash, and quietly suggested that I could put it on the card. I told them I was told I couldnt, and they said you have to be firm about it, and MAKE anyone who doesnt want to deal with it, do it anyway.