Several connected reasons ... primarily because the Blackhawk, like its grandaddy the S-58, has a tail wheel stressed for a landing, rather than a skid/stinger/frange which isn't, and which in any case may dig into the ground and provide no protection to the tail rotor.
Moreover, like most helos, it sits tail down in the hover (and in the case of the Blackhawk, right wheel low on account of the rotor's direction of rotation), so any landing will be tailwheel first - tail, right, left for the precise sequence.
Can also be useful in potential low vis situations, eg loose dust/sand/snow. That then requires a rapid-decleration-get-it-on the-ground-quickly manoeuvre, which of course emphasises the tail down attitude.
You can certainly get a Blackhawk on the ground more quickly than a Huey, primarily (IMHO, having flown both) because of the tailwheel, and of course, if you land with forward speed, because wheels means brakes.