For CEOs, it is easier to for them to pay for somethings than give away something for free. So Google, Bing, etc, should come up with the service for those publishers and charge them like $1000 a months to index their website and list it on the search result. If they don't pay, no index for them. It's now a fair game among the publishers thus they can't really sue Google, Bing, etc for anti-competitive.
Then Google, Bing, etc can compete with each others for lower rate. After a while, one, and soon after that, all of them will offer free listing, and those CEO will jump with joy (we didn't have to pay for it anymore, yeh!!)