The goal is that each end-game player should be able to boost one creature’s stat per week, whether that’s for the 10th Tier or for the first one. Players who want to spend extra time interacting with all facets of the game for extended periods of time will be able to apply more than one boost per week for free.

We aren’t exactly sure what this means, but it seems like there will be more opportunity to get boosts outside of the store. It sounds like the goal is for everyone to be able to boost one stat a week through regular gameplay. Those players that spend extra time in the game (not sure what that means exactly) will get even more boosts and be able to apply more than one boost. "Interacting with all facets of the game" could also mean buying boosts from the store so we'll have to wait and see what happens with that. Hopefully they will have more clarification soon.