Trickle down of course. Those Facebook employees are expected to donate their bonuses to the others in society that aren't getting any help. Isn't that what other companies are asking? People to donate their sick days?
But if that's the goal, why doesn't Facebook just donate the money to an organization that can actually help these people?
I think the comment you are responding to was being cheeky :)
Because then you would be taking away the employee's bonus? Not every employee might be charitable. Probably giving everyone 1k is keeping them within budget.