Any school shootings are to many and it's sad that there might be a market for such an item. That said the number of school shootings you hear tossed around is highly exaggerated and without fuzzy math just plain false.
The def fluid itself doesn't cost close to that in a sprinter.
When I used to add def I got about 10000 miles on about 4 1/2 gallons. At the pump it's 2.79 a gal, by the box you double the price.
That's a ta/petro thing not pilot, the 48 hours. They have changed colors on their cards at pilot/j it is now yellow. As long as he makes sure it says professional driver he will be fine.