The reason why larger booth yields less because developers try to make this game active and addictive for user.
There has to be incentive for players to be active so they made smaller booth to yield more.
You can look at online games, even a game on facebook. They all have this pattern of return on energy spent.
Okay, so I get the rationale, but I also think there might be a better way to make the game active and addictive. For instance, I think the whole sponsorship process could be revamped to do just that. Instead of the automatic sponsorship money we get (related solely to the club rating). It would be pretty exciting if, instead, each club had several key sponsorship categories (sportswear, beer, betting, radio, shirt (logo), and stadium (name), each of which would be filled by imaginary companies. Each week, teams would receive a number of sponsorship offers that may, or may not, improve their overall sponsor revenue. Each would also come with a limited time to accept, between a few hours or a few days depending on its value, or they disappear (or get offered to another club). Even the match ball earns sponsorship money for each home game. Other sponsors might pay cash for each goal scored, or more depending on the number of consecutive wins. Each ascending level would see offers of greater magnitude as well as new types of sponsors, such as sportswear at level B and stadium name at the top level. Either way, users would have to check in as often as possible if they want (additional) sponsor revenue. The potential amount of action here is through the roof!
Another idea would be to sell advertising space. This is a great idea that could even replace (or compliment) the souvenir booth routine. For 20 energy and 1 hr you could "sell small programme advert space" and get the smallest (but most efficient) amount of revenue. Or, you could "sell large programme advert space" for 40 energy + 2 hrs and get the middle amount. Finally you could "sell advertising board space" on a pitchside ad board for 80 energy + 3 hrs, and get the highest (but least efficient) amount of G. Again, the amounts of G could easily and realistically related with team global ranking. Better yet, both of these could be upgradeable, which would raise the amount of G from each option. For instance, the matchday programme could be a 1-page non-glossy, 2 page glossy, 8 page glossy cover, 16 page glossy cover w/glossy insert, or 24 page all glossy (from low to high). Likewise, the advert board could range from a plain wall where ads are hung to a high-tech digital display with graphics, etc.. Each upgrade could raise both the number of adverts that can be sold (per match) as well as the revenue earned from each sale.
Going off the deep end, there's also the possibility that teams could purchase (and possibly upgrade) a team website (within gokickoff). Then users could spend all the time in the world creating their websites, making player spotlights, etc, etc. Prizes could be awarded to best club website, as voted by managers in one's league. Talk about active and addictive!!!
