Wed always thought it was to protect the tank....
but here you go--- I know at least 1 post of a member who tried to jack up the vehicle from this point-- it snapped.
Lifting and Jacking
When lifting or jacking , avoid contact with the Underbody Side Rail (fig. 3). This is for cosmetic purposes only. It hides the exhaust system and fuel tank when the vehicle is viewed from the side.
CAUTION: Besides damaging the Underbody Side Rail, the vehicle could shift on the lift, leading to severe vehicle damage and personal injury.
but here you go--- I know at least 1 post of a member who tried to jack up the vehicle from this point-- it snapped.
Lifting and Jacking
When lifting or jacking , avoid contact with the Underbody Side Rail (fig. 3). This is for cosmetic purposes only. It hides the exhaust system and fuel tank when the vehicle is viewed from the side.

CAUTION: Besides damaging the Underbody Side Rail, the vehicle could shift on the lift, leading to severe vehicle damage and personal injury.