We were looking into these boosts, and unfortunately, they seem to be buggy at the moment. Currently, they are only designed to increase the capacity of your Dragon habitats; not speed up the rate at which Coins are earned.
We'll be pushing a fix for this shortly, and as a result, many players will see their collection rates go back to the normal levels. The Capacity increases are here to stay though
If you really like the sped up rates, don't worry; we might be adding MORE boosts in the future that do just that. For now, we're sorry about the mix-up! Please let us know if you have more questions.