I'm not quite comfortable with the za-zen, shitting-meditation, but some other features and potentialities of this in-vogue phenomenon in the Western world do bother me somewhat.
I might be worried about the buddhist thought's influence and application in the modern world with it's mandatory science-based worry about the future of our planet. Oftentimes it sounds like an excuse of not taking parts and not acting, as long as "my" peace of mind prevails. This is what the marketized version 'mindfulness' may do to many practitioners, and one's own peace of mind in a turmoiled reality might sound like an immoral escape.
I respect Buddhism, https://en.wikipedia.org/wiki/Buddhism, like other sincere and evolved religions, and of course cherish it's updated analytic presentation in the SEP.