i wonder if these buyouts are more or less expensive than severance packages. If you know your severance would be higher than the buyout, why would you accept?

i wonder if these buyouts are more or less expensive than severance packages. If you know your severance would be higher than the buyout, why would you accept? If the buyout is higher than severance, then the company is "losing" money doing the buyout isn't it? I suppose keeping good reputation/PR is worth something...