if you buy something, used or unused you can sell it for whatever people will pay. what they are saying here is if he is affiliated in any way with line, ie owns a shop or is a line rep or something, and gets the skis wholesale through line and does not sell them for the MAP line has set, that is illegal and line could come back and sue him for it or something. Im sure this becomes an illegal act when he signs a contract or whatever with line that will allow him to get wholesale prices.
now if he bought them legit and is just selling them cheap thats peachy because then line would have sold them for the MAP to this guy and then this guy would be losing money.
i believe the pro form thing would be if he works in a shop or something and gets the skis for wholesale prices.