[shmatt]

If they are gambling that the ticket will be worth more in the future (if it was worth more today, it would have been bought by a real customer), they could make millions, or lose everything like Zillow. Guessing what a volatile item will be worth in a month isn't all fun and games

[londons_explore]

They kinda have control of the supply of goods too though - running the main resale marketplace.

When there is an excess of tickets, they can make sure that their own stock sells before random fans tickets ('I'm sorry, nobody bought the ticket you listed for sale, and now the event is over').