[amitamb]

But they are using legitimate means to provide search results. And feed(/API) providers are not shutting them out.

Same argument can be made about Google, they do not produce their own data just copy webpages from content providers. If content providers decide to block them from indexing their websites, Google would be irrelevant.

[ck2]

Look at the twitter token fiasco for an example of what happens when you build your business model on someone else's API.