Yeah I got that. There's a number of possible resolutions, eg selling the widget might be an unnecessary hassle. The problem is we're starting with different sets of premises. As I see it, a rational person considers many factors in the decision to sell good A for $X. The amount he'd pay for it is just one factor & probably the least important one.
In the real world there are transaction costs - but for most people in the example given (college students selling event tickets) they don't come anywhere near $1000.
