Originally Posted by
joefouche
I'm surprised by this -- US carriers normally waive everything if you are buying to a higher class of service... maybe it is a calculated guess on the agent's part that OP was not interested in plunking down thousands of dollars to move up. Or a jump to conclusions, given how many people must ask for a cheap cash upgrade.
I meant the same day upgrades that they discount at check in for extra revenue. I was assuming the OP was not talking about paying full fare and yes I would be shocked if any airline would turn down full fare upgrades to higher class of tickets.