Telling an established business's owners how to run their own business is a big no-no here in the United States, at least as I learned it in business school a while back and seen firsthand in a decade of entrepreneurship. If they don't solicit such criticism, don't give it to them. It's harassment.
Just my two cents.
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P.S. I'm aware Itchio is not an American business operation, but it's on the internet, so I don't care.