Fishing for credit card numbers

Just a little FYI. Last Thursday I used my Amex to shop at 2 stores. When I got home less then an hour later my husband got an email from Amex saying that my account had been compromised. Apparently, a one dollar purchase had been made at Apple I tunes. I guess this is a common practice. A person, program or robot randomly selects the last four digits of your credit card then places a small order to see if it goes through and unless you have a credit card company that alerts you to this it may go unnoticed. Amex has an alert program which you can sign up for. I'm not sure what other card companies do but I'm sure they may have similar offers. Everyone needs to become more vigilant about reviewing their credit card statements otherwise beware!!