If you were to read the advertising spiel on their website it does say they are selling empty seats on private jet CHARTERS. Presumably the aircraft has been chartered from an AOC holder already and the client wants to fill seats to offset the total charter cost?
Interesting idea but I fail to see how it would work. Say I want to go to Milan on Friday? What are the chances of a private jet going from somewhere close to me on Friday to Milan with empty seats and have signed up for this? Not great!
And don't call me Surley.