BBEdit is a small private company, no VCs. They probably make a ton of cash (by normal standards) for the owners at this point and doing right by their customers and not rocking the boat through profit maximization strategies is a long term play that VCs could not put up with.
Plus, BBEdit has a heritage and extremely well rounded and polished codebase. They would not betray their stable business, quality and heritage for some short term gain.
They are building a good product for the fun of it and making good money out of it, which they deserve squarely.