You need to submit for the market, and sometimes it's not what you like.
Exactly. Sorry but you appear to be thinking of stock agencies as some sort of 'camera club'. It's not like that. The agencies only want images that they consider to have commercial potential. Images have to fulfill a need for the buyer __ not the photographer.
Which would you rather produce?
a) Basic image of an apple that happens to sell 1000x
b) A technically difficult image that turns out spectacular enough to hang on a wall but which hardly sells at all
Most of us here would choose answer (a) everytime. There is a joy in providing for the market too and earning lots of money for comparatively little time or outlay. Of course that's not usually easy either which is why it is so satisfying when it works out.