Why doesn't a BMW 5 E60 have a gun in some gas stations in the BMW 5 E60 tank?

This issue concerns only BMW 5 E60 of the European assembly. The safety valve is made so that the owner does not refuel the vehicle with other fuel, such as diesel instead of petrol. Many owners of such E60 in Russia order handsets simulating a handgun. When you insert such a pipe into the throat and open the valve once and for all, you can run the car at any petrol station.