I guess freebitco.in is being generous these days.
The game on freebitco is provably fair, the winning chances of different prizes are known and the result is determined completely randomly.
If a user has won bigger prizes recently, it means that the user has been more lucky. It doesn't mean freebitco has been more generous.
Freebitco is well known for her provably fair gaming system as a casino with prizes randomly won based on gambler's luck, that being said, from I grasp concerning the generosity @Pawanjain is talking of is how out of their own volition they (Freebitco) constantly throw out different prizes for lucky users to randomly win. A habit in my own lens I view as something that gives the community a feeling of a sense of belonging.