You could bring "experience" to the table.
We "older than every member in the band" guys gotta represent.
Way I figure it, why not enter? I mean, worse comes to worse, you lose out. So what, right? However, I have actually considered your other point, which is that I've also had some good experiences and it feels bad to (potentially) rob other people of that. However, I honestly don't plan to win, just to place. I've got the money to afford the trip (I think), especially since it's just a 3 day, 2 night one. Did anyone catch how short notice everything is? You get like a week heads up.
Just enter. I've proven that self-respect is worth throwing out the window.