Not for Scopely's business model, at least for this game. It's not just these events, people spend money on coins, in game cash, loot, tokens and more, and once they start they cannot stop. For wrestling specially, it seems to attract the perfect demographic.
This guy I was talking to, that wants to get rid of the account, has been completely taken over by the sunk cost. Has built his empire of smoke and he's trapped inside.
He's not going anywhere unless Scopely shuts down Champions or someone buys his account, and once that happens that'll be the new whale. For the time being he's still irrationally funnelling money into it, even if at this point it's not really going to raise much its value.
From what I've seen it's incredibly exploitable with fairly loyal customers, at least when they cross the line of no return. They hit a goldmine by putting wrestlers on a gem breaking minigame.