I'm one of those who likes the convenience of plastic. With all those rewards points/$$$ out there to be earned from big ticket expenses like a vacation, I would be foolish not to put it on a credit card. Our final payment for our cruise will go on a rewards card, as will any shipboard charges. It's easier than carrying large amounts of cash or travelers' checks. I should get quite a few rewards dollars for that trip.
However, the cardinal rule in our house is:Pay it off, in full & on time every month! And there are absolutely no exceptions to this rule. I don't charge anything that I couldn't buy with the cash in my pocket or bank account at the moment of sale. But just about anything that can be charged, does get put on plastic. I keep very careful track of all charges and save all receipts. I can also check my card balance online to make sure that I haven't misplaced a receipt or forgotten about an online purchase.