yeah, she probably didn't explain it well, but she's basically right. because it is very difficult to build additional housing and because the local economy is strong, it's essentially impossible to fit in "new" workers because there's nowhere for them to live and there are already jobs for everyone that can find a place to live.
so adding in the 25k amazon jobs doesn't really add in 25k new jobs, it just displaces 25k previous jobs. the value to the community is not 25k new workers, just whatever the difference is btwn the salaries of the 25k amazon jobs and the 25k jobs that would be displaced.
as i understand it, about half of the subsidies are available to pretty much anyone and half were special to amazon. so the 3 billion number isn't really accurate as the cost either.