I work for a public policy think tank, and this absolutely DOES NOT describe us. No one here is just parking themselves while waiting for a gig with one administration or another.

That said, there certainly are such places. I believe a large number of people at the Center for American Progress had very different career plans for 2017 than what has actually played out for them.

There is a very wide variety to think tanks. Some do a lot of serious work. Some are zombies that do nothing but cash donor checks and write letters to the editor. I'm grateful to be at one of the better ones.