Well, all I have to say on the matter is that if I ever catch anyone removing any of my trail markers with a 'Holier than Thou' attitude & lecture regarding my morals/ethics/skill/lineage, their probably going to get a punch in the face.
While I agree they are, technically, litter they're still someone else's property & navigation aids. How would you feel if I smashed your compass or GPS?
I personally get lost very, very easily in the woods. Especially at night & especially in woodland with which I'm not intimately familiar, therefore I use reflective tape to mark my way into & out of the woods. If it weren't for reflectors, chances are I'd never venture into the wilds due to a crippling fear of being lost in the dark. I'll admit, I do remove my tape when I'm finished hunting a particular stand, but that may not be until the end of the season.
Some people simply don't have the luxury of time to get so familiar with all the public land nearby, especially on draw hunts where you only have 2 or 3 days at best to scout & hunt. Navigational aids can be invaluable at times like this.
Learning to read a compass is great, but how many of you would honestly take a few simple lessons & the fully trust themselves to be able to navigate into & out of an unfamiliar patch of timber, to an exact spot? Honestly, not many.