Probably not absolutely mandatory, but if you get a bad load of fuel and let her set up for an extended length of time as I did it would definitely be smart preventive maintenance.
After sitting still for several months, my fuel had the appearance of Coffee, heavy on the cream and sugar with an extremely foul smell with little critters swimming around. Had to drop the tank and swab it out, clean/change both of the prescreen filters, and it still ain't quite right yet.