Why is the wheel bearing grease leaking out of the dust cap?

I learned from years of going very very fast and trying to stop very quickly from 3 digit speeds that the front wheel bearings like 110-130 inch pounds of torque on the nut. Period. This is not some arbitrary number but the result of testing, testing and more testing. YMMV

As far as the rear wheel bearings...0.003-0.005 end play