You don't think it's true that two people maximizing their utility can mutually profit through trade, or you don't think it's true that people are maximizing utility?

If the former, then that's just wrong. If the latter, I think your problem is that you are trying to objectify value. Is your basic premise that since sometimes people spend money on QVC instead of donating it to high-energy physics research that free-market capitalism is unoptimal?