The reason I take jobs in a centralized dense downtown is because I know I can find another job without changing my commute. It also makes socializing after work, or during work, so much easier. I've worked in 5 different offices within a mile if each other in the last decade. I can still grab lunch with people I used to work with within a 10 minute walk of my current office. It is the only reason I am happy to go into the office a couple times a week.

If I worked in a generic office building in the suburbs I would never want to go in.