Exactly. And when I take him somewhere (to the park, to the store, on a walk, whatever), I have to be 100% focused on him and what's going on around us - and that's not always easy. I am constantly putting myself in between and telling people that "No, you can't pet him." and "No, don't touch my dog." And it gets exhausting, and it gets stressful. And if something that says "Don't pet me." stops one person from approaching him and trying to pet him, well, that's one less person that I have to deal with. A vest/patch/whatever is not a magic fix-all, it's just an aid.