Apple's official monitors double as docking stations, with USB/Firewire/Ethernet being carried over thunderbolt.
The most recent ones also half a decade old and still quite expensive, so I can't imagine buying one, but Apple would tell you that they do have a first-party docking station, complete with monitor built-in!
You could simply add a Thunderbolt or USB 3 dock....
Using an external keyboard and mouse solves the ergonomic problems of using a laptop for long periods. (Sad to say, I see very few people actually doing this.)
Of course, you don't get the benefits of running a faster, hotter processor, expandability etc, though Apple no longer offers a reasonably priced tower system anyway....