They are probably focused onnither things or you're just far from them, this is more of a blessing though.

I always see them sprinting around , other times I am in a shootout with them.But they never seem to charge me , only kick me when im in their face

^ that's why

I guess its just a coincidence

I didn’t get the achievement for getting kicked by a cloaker until I was about level 50 ish which isnt surprising but still