I'm willing to bet the OP has never dealt with them before. John and Pat are pretty easy to get along with and there are a lot of tire kickers out there that say they will, then they won't.
Usually in such a case, the store will ask for a credit card number and only charge the amount requested for the article when the store receives confirmation from their supplier that the item is available, and the credit card is good for the requested amount. Not a biggie and I wouldn't blame a vendor one bit for doing business that way. Especially with a total stranger.