Is the monorail crafting now endless?

I stopped in games 1 & 2 after a couple of rounds. Trying to keep track of what I needed in all 3 games was making me nuts. I kept going in game 3 and I'm bringing in 10 to 20 extra donuts a day depending on the projects I get. If I get a good mix then I breeze through, but if I keep needing the same thing I get bogged down.
I'm grinding mercilessly in game 3 to get as many donuts as I can for chances in the Halloween and Magical Mystery Boxes. I'm determined to get Marge the Witch this year so I'll have her in all 3 games and I want as many other things as I can get.