Actually, the hub itself can be bent slightly, while the bearing is still good..
If the wheel experienced any hard impact it could have slightly bent the hub. Although it would most likely end up destroying the bearing as well..
Im pretty sure Im actually experiencing that now..constant squeal after a brake change..I had a hard impact on the driver wheel hitting an island early last year..and changed the bearing last summer (race literally fell out in my hand after taking the rotor off)..but didn't notice till now that the wheel isn't rotating completely true. CV joints are good, rotor is good,bearing is still good, no joint movement... but watching the brake caliper on the hub you see some uneven motion, making the rotor touch unevenly. Only thing I can sum it up to is the hub being slightly bent..just don't want to pull the hub and thus doing another bearing change again right now to see if my suspicion is right...