I posted a similar pic, from a local propane distributor. Seal to EMT to PVC at ground level. This appears to be a far more common practice than I had thought.
Having learned about this stuff in the oil / chemical refining industry .... one wonders! The code speaks of 'qualified professional' .... and we see this thing that flies in the face of all logic.
I do wish someone would write a "How to" book about classified locations .... covering not just wiring practices, but defining the "zone."