Well as for the past question i think you already have an answer.
As for the last one:
To avoid fraud, is like when Youtubers use bots to pump their numbers (i’m talking on donating big amounts of BAT).
Here are some past quotes from a team member
Due to the comments on that thread, is fine to self tip your montly earnings (i repeat according to that thread since advice of @Asad) but self tiping, for example, 600BAT acummulated from the past two years lets say, well it can be checkout and can result in a suspended or reviewed, this to detect abuse of the system or bots.