I do but it seems frowned upon by the cognoscenti.
3-4 offroad rides per week and at least 2 (sometimes up to 4) bikes to wash each time - bucket and a sponge ain't gonna cut it timewise.
I stay away from hubs/bb/headset/pivots etc. Recently I tried an experiment on my Hardtail by steering clear of the rear hub but blasting the front hub directly on the seals as much as possible for a month's worth of washes. Serviced both hubs(Shimano) and the front didn't appear to have any less grease in it than the back. The grease in it seemed ok property wise.

