Yeah I'm starting to think that there is some sort of misunderstanding so I'll try to explain what I meant again. This time with a better understanding. (I hope)
I just don't think it profitable just to stick to one platform for VAing, or in this case one show. Sure I understand that if their acting gig is steady enough they don't need to job hop, but it good parachute plan to atleast tryout for other shows instead of sticking with The Simpsons. Cause who knows when that milk from the cash cow will dry up, or when the studio decides to call it quits for them (though I find the latter highly unlikely, since it is one of three things FOX has been constant with over the last 20 years or so). Unless their contract forbids it, which I don't think is possible, since I atleast seen Nancy name in the credits of other shows, and I think Hank works in Live Action field. I just don't see people like Tom Kenny for example, only working on Spongebob, he voices for various other cartoon, whenever it be one-line thing, or another main character on another show.
In the American anime market case, I've been noticing for a while that most VA for them switch between Texas and Califonia market since the New York one is rather dried up, and more money could be made in California. I thought they resort to doing that for the pay so they can support themselves and their family lifestyle, though I am questioning for some if the studios pay for their plane ticket or not for those who switch between Texas and California. Also since they're non-union, I'm not sure how much that holds up though.
I know that the Simpsons has a higher budget than most animated shows on the airwaves, It has to be a given with their animation has evolved, it's in Prime Time, and the fact that a majority of the people who work on the show are unionized, otherwise it wouldn't have been affected by the strike. I support the Simpsons VA looking for a better pay.