Well, there's a number of ways you can look at this. The following comes from the Ayahuasca Manifesto that was posted here a few days ago:

This is my time to embrace the planet. It is my duty. My mission. What I was created for. I now become a protagonist after remaining in the shadows for thousands of years guarded by my indigenous protectors. They now travel around the world raising awareness about my benefits. It is my duty to assume new cultural expressions, very different from those of my beloved guardians of the forest. The rituals, the "icaros", the “dietas”, and related knowledge should be preserved as an endowment of world heritage. A legacy to the Universe.

Similarly, my new ways of expression, the manifestations that are taking shape in different world cultures should also be respected and recognized. I am already manifesting new urban modalities and forms like never before. My spirit exists beyond the forms, beyond the cultures, beyond man himself. I am connected to the spirit of the planet and beyond, cosmically up to the central sun of all the existence. Just like the sun with its life giving warmth I should be equally available to everyone.

So yeah, one on hand, one can totally understand the frustration curanderos might have with tourists coming in just to get high. On the other though, they have access to something so powerfully healing--who's to say it belongs to them and them alone?

Life is ephemeral. It's sad to see customs and traditions slowly die, but on the positive side, what might grow in their place?

Intent matters, and so long as there are healers out there intent on healing, I imagine that aya will prosper, in one form or another.