Many may question why anyone would take an office with facilities included with other companies there too?
Well today with the ever rising cost, building an office with the tools you need would be best with the economies of scale. Meaning if you could maximize the usage of all the facilities.
Also if you are a one man or few man organisation, whose main concentration is on his specialty such as sales, tech deliveries, consultancy and many more. You would not want the difficulties nor the complexities of the day to day running of the administration. As such you will want to out source it too.
Another part would be the business network possibilities when in such an environment.
The possible reasons just go on.