The many times I've thought this through, I've always tried to think of ways to make sure publishers get their due. The question is, how much IS their due, and what can you do about it. If sales are decreasing for them, I'd want to make sure they get something back out of it, but cash isn't always an option.
Of course, in my model, the more open the publisher was (in regards to giving proper OGC declaration, ability to put small bits of PI in for 'advertising', etc) the more they would get in return (bountiful amounts of links to their products/online store/etc).