The question itself demonstrates you are a good 10 years behind technology in your mind and you need to catch up. No offense intended, docking stations went out when USB became cheap and reliable. They are LONG gone.
I disagree. Our office uses them every day with great results.
We have a bunch of Dell laptops at work (ATG D630s, M4300s, and M4400s), and maybe 15-20 docking stations. They all work well, although I will say that we've had to have a few returned under warranty.
Having the laptop allows our guys to work on the road, in the office, and from home using the same computer with a minimum of hassle. We had a few extra docking stations sitting around awhile back, so some of our guys snagged them (along with a few extra monitors) and set up a workstation from their house exactly like their workstation in the office.
Each docking station is connected to a dual (or triple) monitor setup, and each station has it's own power brick (plus one that some of our employees have in their travel bags for a total of 3) –– this allows the user to disconnect the laptop from the docking station at work, bring it home, plug it into the docking station there, and work from home if they want without changing anything. Heck, they don't even have to open or close their laptop in the process. Then if they need to go out on the road, they have a laptop they can bring with them without any hassle.
There isn't really much of a downside other than the usual issues of laptops not being as powerful as their desktop counterparts (really only applicable if you're doing CPU-intensive work like CAD or SolidWorks), plus the up-front expense. Docking stations aren't cheap but they work nicely for their intended purpose.
For those of you saying that you can do the same thing with a USB hub and a monitor cable...eh, it isn't the same.
The docking port allows me to disconnect or connect the entire laptop in about 2 seconds without messing around with a bunch of cables (plus it allows me a full dual-screen setup, instead of laptop + 1 screen). Some of our guys even have a full dual-monitor setup plus the laptop screen using a Matrox DualHead2Go system.