On my recent trip to the US, travelling from STL-ORD on a discounted economy fare on AA, when checking in (using a kiosk ) I was offered an upgrade for USD $45. As it was such a short sector, I declined. I also I assumed I would still only earn status credits for my orginally ticketed fare, but still, being the US not 100% sure. So question is has any one experienced this before? And was my assumption correct, or did I do my self out of 50 SC's at the price of about $1 AUD/SC??