No 2-stroke gas-powered tools should be stored
with gasoline inside. (They should be run until dry,
i.e. until they stop from fuel exhaustion.) The various
chemicals in the gas/oil mixture gum up the carburettor
if sitting there for months.

Pardon me for interrupting..

Why don't they have fuel valve? It would be quicker and less wasteful to run
dry the carbuerator than to run dry the fuel tank.

In case of cleaning up storm damage (e.g. fallen tree), a gas chainsaw may
be more handy because the power may be out due to the storm.