Right now, neither of them had reached 30,000 power, even though they were close. And that was because their abilities had restrictions that didn't explicitly say so but were evident when they were in those predicaments.
After passing 25,000 power, neither of them could get power from people with less than 10,000 power.
In Alice, it was fine, as she could still get the additional percentage after killing people with 10,000 power. However, in Matt, there was a possibility that, in the near future, the ability would stop working on people with 10,000 power, which was frustrating.
Although, in part, it made sense. Even if they are growth-type abilities, at the end of the day, they must be coupled with the world's laws. The world will not allow gaps between the balance of races and growth-type abilities, in part, to break that balance. That is why the world must put restrictions on it.
'It's unfortunate, but there's nothing I can do.' He thought and sighed...