Just put some new All-Balls wheel bearings in the rear wheel tonight - will do the front tomorrow. Anyways, got to wondering and decided to pop the bearing open and see how much grease they came with from production and was shocked to to find so little grease. I expected they'd be shy on grease, but not almost void of it.
You can use a very small paper clip (one of the rounded ends) to insert under the inside diameter lip of the bearing seal to gap it open just enough to slip a very small jewelers screwdriver under the bearing seal and pop it out. Take it slow and be very careful or you CAN damage the bearing seal.
Once the bearing seal is out (as in the pic below) pack the bearing with grease and pop the seal back on and wipe the excess grease off the bearing before driving it into the wheel. Residual grease left on the bearing will only server to catch dirt/debris/small metal shavings/etc... as you drive the bearing into the wheel.