I wrote a reply about what utility means but it got lost to the abyss. I'll try again.
Skimming this wikipedia article
http://en.wikipedia.org/wiki/Utility may help a bit more, but I'll sum up how I think of utility.
When talking about some amount of money X, the utility of X for person Y simply refers to how much use (or utility) they get by either having or being given that amount. For example, the utility of $10,000 to the average person is much higher than the utility of the same amount to Bill Gates (since he's mega rich). Similarly the utility difference between $10,000 vs. $9,500 is not going to be very big for most people (though it will still be a bigger difference for less-rich people).
In the example of poker tournaments, if a bankrolled player is playing at reasonable stakes, then a min-cash normally will not present an overwhelming amount of utility to them. Some, but not a lot. Therefore, they should never really be sacrificing EV (a larger average payout) for the sake of a min-cash or small pay jump (lower average payout at a higher frequency). However, once pay-jumps (and therefore utility jumps) begin to get large for people, they will begin to take lines they KNOW are -EV for the sake of a greater chance at a guaranteed reasonable utility gain.
In particular if the EV sacrifice is small and the perceived increase in probability of gaining some utility is large, then people tend to do sacrifice the EV as a no-brainer (rightly or wrongly, I wouldn't care to judge). But always remember that getting a larger ITM % will often mean a decrease in average payout for a lot of people.