Yes, the bike is a 2008, so I can understand them demanding full msrp. Good thing I'm not buying a car, eh? As for being pushy, I don't think I was, but I suspect that many retailers look askance at bargain seekers. By the same token, I don't know how many folks walk in off the street and pay full list on bikes. Is it insulting to ask if there are any winter sales going on? Just asking....

As for the bike being the wrong size, I was under the impression that stem length was one of the three things that are commonly adjusted in order to find the right fit, the other two being seat height and fore/aft placement. Does needing a shorter stem automatically suggest a wrong frame size?
Is there anything about the bike's dimensions that lead you to this conclusion? Heck, the 50cm top tube is only 10mm shorter than the 53's.