From CS Rep to Postal Agent?

Customer: I want to know when I'm getting my phone.
Me: May I have your order number---
Customer [cuts me off]: I mailed a money order on Friday to you. When will you get it?
Me: Umm, what?
Customer [with an attitude]: when will you get the money order?
Me: Uh, ma'am, I don't know when we'll get it.
Customer: Why not?
Me: Because I don't know where you're sending it from, or how many stamps you used. First class mail can take up to 4-5 business days to reach its destination
Customer: But you're supposed to know!
Me [losing patience]: Ma'am. Once we receive your money order, we'll email you to let you know when your item is shipping.
Customer: but how long will it take?
Me: However long---- it'll take about 5 business days.
Customer: I don't know why it's taking so long. Thanks. [hangs up]

[here comes the rant]

First off, I'm NOT the post office, OK? I have no control over how long it takes for something to reach here. Secondly, if you were so concerned about how long this was going to take, you should have paid with a credit card.

Gahh. Mondays! >__<