I hate

Walking on shared-use paths and glaring at you when you have the temerity to want to use a tiny bit of it yourself while they selfishly cause undue wear and tear to their pets paw pads and joints that would not happen if they used the adjacent lawned area?
Yeah, me too.

I've had one tangle and a couple of emergency hurdles/stops with these little skinny leads. Tiny often yappy chasey Rodents on the end of a near invisible 10ft tripwire whilst the owner spends the entire walk staring at their phone.