Im going to be odd one out here and say I have been burnt badly by the "just in case" swipe. They did charge it, without my permission, they meant to charge someone elses, it was $780 so not a small amount. Yes I got it back but it took ALOT of effort on my behalf.
Whilst you cant get around places wanting a credit card, you can just open a seperate account and have a visa debit card used specifically for this kind of purchase. I use mine for paypal and bookings and for deposits, always just transferring the money over as its needed. Limits the financial implications for someone elses mistakes and limits our risk if the details are stolen or misused.
Our direct debits are also taken from this account (an auto transfer is set up from out main account to go into this one 2 days before the dd is due), I have had a phone company keep taking money after I cancelled the account and the bank wouldnt stop it either.