Examples of walled gardens that many people use are Instagram, FB, even Reddit to some extent which hamstring their mobile sites and push you to an app.
I couldn't get out of all these either but I keep them strictly separated in Firefox tab containers. I think it works because Facebook always suggests friends to me whom I don't know at all, and its ads have no relevance to me (only to the 1 or 2 topics I use FB for).
