These sites are really at odds with teams who have chosen the leasing vs. ownership of tickets, where leasees can only transfer and sell their tickets on the of

These sites are really at odds with teams who have chosen the leasing vs. ownership of tickets, where leasees can only transfer and sell their tickets on the officially-sponsored marketplace. I'm a season ticket holder for such a team, but can't go to all the games, so I list quite a few each year, and I really hate that demand for tickets gets unequally spread through the official market and these other markets. Is there a legal reason why a seat aggregator like SeatGeek doesn't list these official site tickets? Is it just because they don't get a kickback from them? Some other reason?