Besides plumbing, one thing that came up on a similar discussion in the subreddit for my local area was that there the codes are different between commercial & residential in terms of how far away a room can be from an exterior wall. And it's not uncommon for commercial buildings to have a lot of space that would be unusable in a residential setting because of this.
Not really. Most of these kind of offices have either a raised floor or suspended ceiling, making the addition of this kind of service trivial, compared to doing it in residential buildings. Natural light and fire escapes will be more difficult to provide.