I used to take a Dak regularly between Grand Reef and what was then Salisbury in Rhodesia. The old Gooney bird had to fly very low for part of the journey to avoid rockets, which meant getting bucked around a lot by thermals.
So, on a trip with newbies, some of the infantry guys would fill one of those green NATO airsickness bags with fruit salad, and once the plane started the full roller-coaster bit and the newbs were looking a bit green, he'd pretend to barf into the bag.
Then he'd pass it to the person next to him, who'd take out some of the fruit salad and start to eat it. We had to stop doing that eventually because too many newbs didn't get to their own barf bags in time.