1) They were heavily incentivized for leaving. If you even considered a carreer move, the 6 month severance is your call to action.

2) I don't know that them leaving is so bad. They disagree, they leave (with generous compensation), not a huge issue in my book. Everybody is being treated fairly here, it seems. But for some reason, people have to insist that basecamp is evil, while to me it looks like they're going above and beyond the call of duty to treat their employees right.