I do not know about their harvesting practices. I suspect the worst. I remember the depressing day when I was cleaning sticks and leaves out of my new bale of north american Sphagnum , and pulled out a dead and dried Sarracenia purpurea plant. Ever since then I have been looking for Sphagnum alternatives. It seems successful.
Some carnivorous plants prefer undecomposed strands of long-fiber Sphagnum .
Some plants even prefer live Sphagnum. Finding long-fiber Sphagnum to buy may be difficult because few nurseries carry it. This stuff is garbage, and is certainly not Sphagnum , despite what your well-meaning nursery staff may think. Nearly all nurseries think they have Sphagnum , but what they usually have is peat moss or the useless green moss or sheet moss materials. Equally useless is material known as sedge-peat, which I understand is available in Europe.