Yep -- I'm not one to go throwing money away on Marine parts that are the same (or good enough") as the auto ones, but you can't and shouldn't be using the auto version.
And to the guy above that said he just pulls his doghouse cover off to "air out" the gas fumes -- gas fumes are heavier than air. This is why you MUST have a marine starter. Gas fumes/vapors will sit down low in your bilge and if the conditions are just right and there is a spark.... boom!
Always run your blowers. Always use a marine starter.
(And I'm one of the few that's comfortable using an automotive distributor. The fumes/vapors would sit too low for that to cause a problem. Hopefully!)