They're perfectly fine where I'm the only one who touches the card, such as in the supermarket checkout line. It's way less hassle than writing a check, and easier to get a few bucks back in the transaction so I don't have to hunt down an ATM.
I’m sorry to tell you, but even in the supermarket, you are not safe from this type of theft.
http://www.boston.com/business/globe/articles/2007/02/19/stop__shop_reports_credit_data_was_stolen/
The Pakistanis who did this flew all the way from CA to RI to pull this caper off.