Very true tonedreamer and the exact reason I finally decided to use the thumb pick in the first place. If youre a true finger style guy, the thumbpick is just the most natural progression. It feels too long and gangly at first, which I why you hear of so many guys sanding them down.
But after awhile, you don't even have to sand them down anymore. When I first started using a thumpick I used this one special brand that had this little tiny knob thing that came down from the thumb wrap around part of the pick, plus had to sand it or it felt terrible. Now I use National full size thumbpicks and they don't feel too long anymore. It just took about a year of consistently using the thumbpick for it to no longer feel weird.
Now I use the heavy National traditional white thumbpicks. Its perfect because its long enough to act just like a regular flat pick when I need it to for stuff like ZZ top and all those pinched harmonic tones. Or any tune that requires that full picking tone. Or some that are so physical, its too painful to do without a pick.
I do agree ZZ top isn't very good without a pick. Ssame can be said for some other guitarists too, like SRV tones as well.