Who is this mysterious man in a lab coat. What does he do with the pokemon he takes. Does he sell them to others or use them to perform illegal experiments. Why dies he want to buy pokes when he can catch them. Hmm.
Just a joke
Maybe Prof Aspen is a Latias/Latios/Ditto/Zoroark and is trying to Free those Pokemon you sell and the Cash comes from a Hoopa in the Group who gets the Cash using it's Portals