The engineers are not getting that obviously, it depends on how much equity they have and the difference between the amount of VC money pumped into a company and the final sale price of the company. VCs often get 2x preferred stock (at the minimum - it entitles them to 2x what they invested). This is before anyone else is allowed to see a dime. Every term sheet is different of course.

The value of the team is also larger than the individual engineers on it. Plus, a package bid is less risky if you're looking to get the entire package.

Oh, and poaching has another risk - that you get only the worst employees.