as you said, cool but not practical, not to mention that the shape and diameter of the faucet in addition to the diameter of the tubing plays a big part in pouring a beer with proper head and without degassing carbonation.
IIRC, the tubing inside an in-door water dispensing is very narrow - that's going to be a big problem trying to pour a beer at say, 10 PSI.
I don't think any of your friends will think a nice perlick mounted on the door is any less cool
