Let me correct your statement. No, that is inside of the garage where I work. I backed the tractor I use for work in there, after spreading salt, the blue stuff you see on the snow is from the salt I was spreading.
It's definitely a lot better when it's just straight up snow and can leave it in 4hi, compared to on and off snow and bare pavement mix. Sand / weight in the back made a huge difference for me.
Yeah, I didn't notice the issue on mine until it got well below freezing. Have you tried manipulating the boot at all, like maybe it's just folding wrong?