Simple, do you want gambling in the game?
Also maybe even some cool mini games to pass time.
Gambling was a really big part earlier history and still is today. There's no reason that they couldn't add in games that people could bet on. Maybe some time of Guar racing where the players have no control of the guars so it's all RNG based. Or they could add in obstacle courses that people have to race through and people bet on the racers.
IF they ever add in Arena's to PVP they could easily create a Colosseum that people could watch these fights and make bets. I even suggested this over a year ago....
If people watch these games, you will have massive lag due to so many in the same location nearby - and this would make the combat in the arena less performant. Same goes with gambling - I just think of how gambling was, when it was still a part of second life - it was horrible, gamblers caused lags in every region, where they started to gamble. I am against it.
Oh, so you mean like the game exactly is now in Cyrodil...... And I don't think it would lag the game worse that it already is. If they did a Colosseum based setup as instanced, there would only be those players fighting in the Arena that are casting spells. Everyone else would just be spectating placing bets. The game would run perfectly with 200 people on the screen at the same time if only 6 of them would be casting spells. @ZOS would have to adjust the server calculations to only affect those players within the actual Arena but that should be doable.