Well, was a stranger in a center hundreds of miles away with you when a purchase was made?
Regardless of the business or industry, no one is psychic. All anyone can see as far as purchases go is an amount and a date. If they can't see that, not much to go off of.
Instead of acting like Verizon reps are stupid for the above common sense, don't save your credit card information on sites where purchases can be made.