"Pretty weak story. Never had an apartment with a hot water heater of it's own, much less a gas powered one. Did have 1 (out of 10) that had it's own electric hot water heater. My current condo has a gas fired unit, but it's common to the building."
Well, it's getting more and more common to have on-demand hot water heaters in apartments and other rental properties. My office building in CA had one in each bathroom, just to heat water for that room. It was gas-fired.
Have to admit most of my living experience has been east of the Mississippi. Where most buildings are pretty old. My condo was built in the early 60s.
The new on demand hot water units do make sense (thanks to size) in units thanks to their size.
Your point is well taken.
Well it certainly maybe more common to have on-demand hot water heaters, but they don't have pilot-lights like the old water-heaters and furnaces. All the "new" (at least the last 10 years) units have piezo-quartz electronic ignition.
That's not to say the flame on the burners couldn't ignite something, but it seems to me that you couldn't get the concentration of gas needed for ignition from the small amount of gas (in liquid form) brought in over a lunch break. There isn't enough time for evaporation. Something about this story doesn't smell right (sorry for the pun).