If you were going to delete it you wouldn't leave the vent line running to the engine bay anyway, just terminate it at the tank with a one way valve in it to stop fuel spilling out in a rollover.
There isn't a fire danger if it's done with a little care, and like I say, lawn mowers vent to atmo and they don't seem to spontaneously combust........
I wouldn't worry too much about the vapour, remember cars running rich AFM blow unburnt fuel out the pipe, and carbies with bowls full of fuel sit above/beside a hot engine. It's not really an issue.
