I will say it again, I don't have any problems with using paper shreds in my chicken coop because they are basically out of sight. When I toss the spent paper shreds out into the chicken run, I either dig a trench in the compost and cover them over, or I toss the shreds into a pile and dump fresh grass clippings or leaves on top of that pile.
I don't like the looks of paper shreds out in the chicken run. I prefer to see natural look of green grass clippings or leaves. So, I cover or bury any shreds I dump into the chicken run. Also, if I don't cover the paper shreds. a good wind will blow those shreds all over my lawn.
One big advantage to covering the paper shreds in the chicken run is that they will compost all the faster. Composting litter in the chicken run is my main goal, and paper shreds compost much faster than either wood chips or leaves. But I mix in all organics and just let them compost together.
If you shred brown cardboard boxes for the coop litter and then the chicken run, I think that would look just fine without having to cover it. I guess what I don't like about the paper shreds I use is the multicolored shreds don't look "natural" outside. Maybe someone would like that look of multicolored shreds in the chicken run, but I don't.

My old hands would feel the workout if I had to cut up cardboard with a manual scissors for any length of time. I currently don't have much heavy cardboard to use as paper shreds, so I have not invested in a battery powered scissors/shears. But it would jump to the top of my list if I was going to use lots of cardboard for shredding. It would not take long to pay for itself just in ease of use, productivity, and saving myself from sore hands.
Also, I think using a powered scissors to cut heavy cardboard into smaller strips for the credit card slot would add years of life to a home paper shredder. So, not only would you give your hands a break, but you would also be helping your shredder, too.