The game's already satisfying. It's the best browser-based football manager I've played.

Does it have room for improvement? Sure. So does Madden, and that only costs $50M+ in development every year.

It is already satisfying. I like the product and I'd like to see its creator profit from his labor. Idk if he even has plans to do anything like this in the future, but I hope that whatever plans he does have, work out the way he wants. I cant imagine that he wouldn't like to reach a larger audience and make more money, which would likely happen if he did create an app. Maybe he doesn't want the extra headache, idk.
I like the game. I'm spreading the word to my friends.

Am I the only one bombarded with interstitial ads and sliding billboard ads when I look at the site on mobile?

That went away when I bought credits. Then, came back when I spent down to less than 6 credits. It went away again when I bought more.
Small sample size, but I think there is a correlation.

It's as if he's already profiting from his labor.