Agreed. The same argument could be made for hiking, kayaking or any other slower form of travel, with the other side benefit being no green house emissions. However, the logistics and planning behind these forms of travel make them less appealing to the masses, especially for those just getting started (with the exception of tours and the like). Certainly more could be done to simplify matters for those looking to go it alone, especially in Europe. Just look at the Eurovelo site. A great idea, but horrible in execution.
In Rio, they do guided trips into Favelas. Back before my "travel blogger" days, I chose not to do it, ultimately because it just didn't feel right. Going in to gawk and take photos felt more like a zoo experience (like you mention John) than a human one. Although, I think tourism like this could be setup differently, where you are not bussed in and out of the area back to "safety" and could be something that I could get behind (more of a cultural exchange or perhaps even participating in community projects). It may be the fact that the tourist is just popping in and out, like it was a attraction akin to bungee jumping or, for lack of a better example, a zoo. You can hardly get to know a culture in 3 hours.
Amazing photos. When I look at what these guys did and how many shares received on this post, it boggles my mind. The content and adventure here is humbling, yet they only have 1,400 likes on their Facebook page and the post itself had 16 shares. Something to think about... content alone won't get you an audience. Major props to these guys in any case.