My hatch stays locked,,,,not sure how anyone could steel it. If you tried to pry it open it would surely crack or break and be useless anyway...
If you keep the hatch locked,,,I really don't see anyone taking it. Honestly though, the hatch has never been my concern,,,I've always been worried about the truck itself as a whole
Lot's of relatively easy things you can do to prevent theft though, or at least slow them down enough to draw attention.
Hidden key lock switches for the ignition power and fuel pump are good ones,,,,just sayin'