Wait, I just read that it was 2:15 PM! You realize that most Post office's close at 4 or 4:30. That wouldn't even give someone 2 hours to get to the P.O.! And if they are mailing from their house, then my mailman runs at 11 am so they would already be gone. And its kind pushy to "expect" Sat. service from anybody.
I don't mean to be hateful or anything, but really, that is unrealistic expectations. All companies that I've dealt with online (and thats how I do all my shopping) do their shipping in the mornings.
As I said, you basically got next day shipping, so I really don't understand why you are so upset. If you ordered from Walmart.com that late on a Friday,there's no way you would expect it to be shipped that quick, which even if you included the Sat. would within 6 hours of ordering! Not even a full business day!