Looks like something military folks do on dares etc.
The stories the military members of my family tell about the dumb things they would do to kill time and entertain themselves could fill volumes.
My thoughts too... Someone trying to get a good tik-tok shot...
My Dad talked about Jeep races on the beach while convalescing at Boca Chica Field toward the end of WWII.
I was originally in artillery and never heard about or saw anyone do anything for fun around the guns.