But I am never happy finding trash. And I wonder at the folks who leave it in nature. I have been out on rocky beaches and up high in mountains and come across trash, trash that was deliberately discarded. All too common now, I come up to a great view ... and empty, discarded water bottles. This is a sad thing that people cannot take their own bottles out. I have found them deliberately stuffed down into cracks in the rocks. These things are not going to decompose, they degrade the environment and the experience. Plus cloning them out of a photo is annoying at best.
So I generally pick them up, crush them and put them in a pocket. They have no weight so they have no effect on the rest of a hike. Why they would be trouble for anyone to take back, I have no idea.
I often pick up trash found when I am out photographing. It is a shame we have to do that, but I hope you will give a thought to keeping our natural areas looking their best, too. I now keep a small trash bag into my camera pack just for this purpose.