You don't buy the "Mona Lisa" , then enter it in an art competition !
I use to build "for profit" and, YES, I would be Outraged !
I have had the opportunity to see one of my build's for sale at a Train show ( I built a 1/87 scale steam crane and sold it for $300.00 ) At the show ,a vendor had my crane in a case ,for $450.00. I can only hope that the guy I built it for ,10 year's before, didn't loose money on it.
I went back to the vendor's display later in the day, and it was gone. So it's nice to know my work is ,at least "sought after"..