I meant the big manufactures, like Fluval, Roma etc
What's good for the stores is usually better for the manufacturers, who usually get a bigger cut out of every sale than the retailer.
Short of full-blown MTS, an informed hobbiest spends less than the type of fish buyer I mentioned above, both initially and for maintenance. I bought a tank, stand, test kit and filter my first day in, and came back for a heater, gravel and rockwork, and plants two weeks later, and three more weeks later fish and food. From there it's just been food, occasional fish (which my LFS tells me isn't very profitable for them in general), and once in a blue moon some meds. My LFS spending rarely breaks $15 in any given month unless the test kit needs a refill.
Going on bad advice, somebody can walk out of the store their first day with everything I did in three visits over a month, plus too many fish and $50 in random chemicals they don't need and probably shouldn't use, and if they don't give up will likely continue to buy filter cartridges, chemicals, and will likely replace fish at a higher rate than I have to.
If they can be hooked with zeolite like my aunt was, they can end up spending $30 a month just to keep ammonia under control, and armed with the cycle instructions that came with their equipment and the bottle from the store that says they'll only have to do water changes once a year, they'll be dependent on it once they start.
So, there you go - it's just capitalism. You cater to the customer who spends the most money. If group A drinks 500 bottles of coke a year and like it, but group B drinks 5 million and think it needs something new, you cater to group B and will let group A buy Pepsi if they don't like it. If you catered to group A and started losing group B's business, the investors will jump ship and the company will suffer.
Not the best analogy I guess, but it works for what it is. And in this case, group A may not like it, but they still have to buy what they do use, so there's no need to struggle to keep these customers, and there's definitely no percentage in converting high paying group B customers into low paying group A customers, even if group A is happier.
Edit: In retrospect, the example works better if group A thinks it needs to be changed and group B is happy, in which case Coke would continue with the status quo.