Grrrr to the Post Office

So I have had some annoyance with the United State's Post Office. This past Tuesday I put my Sabrina's birthday card in the mailbox to be picked up and it didn't get picked up until today, which is Friday. So it took the mail carrier 4 days to get my mail. I think that this situation would annoy anyone. The sad truth is that this is not the first time it has taken many days for my mail to get picked up, this is a reoccurring problem. I have been urged many times by Hillary to call and complain to the post office. I finally followed her advice and called yesterday and received some rather frustrating news. Apparently because I live in the city if there is not any mail to be dropped off the mail carrier is not required to stop and pick up the mail. If I lived on one of the rural routes with my mailbox at the road, not requiring the mail carrier to get out of the vehicle, my mail would get picked up the day it goes out. The lady I talked to at the post office said that routes are already too long and that is why they have the blue collection boxes for those in the city, and if the mail carrier has to walk up steps to get to the mailbox they don't have to stop if they have nothing to drop off. My response to her was that first it is absolutely ridiculous that they don't have to stop. Second, my mailbox is at the bottom of my stairs so there are no stairs to climb. And lastly since when is it not the job of the mail carrier to pick up the mail and carry it to the post office. I did not receive a satisfactory answer from her and I know that my complaining won't make a bit of difference. Is this a normal thing to happen for those that live in the city or is it just the great city of Flint? I am obviously rather annoyed with the post office and the whole situation.