Dear Guy In Front Of Me At The Post Office:
I'm sorry I was so rude. See, your taking 20 minutes at the self-postage center just to mail one package made me think you were incredibly stupid. Now that I'm reflecting on the situation, I think you may actually be illiterate, instead of intensely pondering the possible answers to each question the postal calculator was asking you (my original assumption.)
None of that matters now, though. Because despite your deliberations over insurance and proof of delivery options, you stupidly did not check to make sure your package could fit in the slot for the self-postaged packages. You blatantly ignored (or, again, perhaps could not read) the giant red sign that says "Please make sure your parcel fits down the chute before tying up the line with your asinine antics, ass."
So when you tried mailing your shit, and it didn't fit in the basket, and you shoved it in there anyway and jammed up the lever for the chute -- thereby making it impossible for anyone else behind you who had already purchased postage to mail their packages until the next morning -- it certainly could have NOT been your fault. You could quite possibly just be illiterate, instead of a complete asshole.
But probably not.