As others have mentioned, the amount that someone has available on their credit card is irrelevant to the real problem, which is 'full disclosure'.

I don't use debit for hotel stays & find that holds on credit cards can take 3-7 days to fall off, both upon check-in & check-out. Usually the hold lasts longer on an int'l stay, but occasionally I have a long one on a domestic.

And as someone mentioned, if you're on the road for a long time & haven't had time to process expense reports, even large amounts of credit can get eaten up.

BTW - for those that think Amex is 'no limit', you're wrong I believe. Your limit is based on your spending pattern, an Amex rep told me.

FWIW - I think disclosure on holds should be on each reservation so that people know/can plan accordingly.

Cheers.