Ask To Pet — be a responsible dog lover

I have a Cocker Spaniel puppy, Harington, who I am training to be therapy dog. We are very regularly harassed by people wanting to cuddle, fuss and touch him in a state of puppy-induced hysteria, often leading to an array of appeasement behaviours. One of the worst experiences was someone who picked him up when he was out walking and on lead. None of this makes for a positive experience for a young puppy trying to learn about the world. I have now resorted to walking him in a vest with badges on such as ‘in training’ and ‘please ask to pet’ as well those from Yellow Dog UK. In fact, I probably have the title of the least friendliest dog walker, all because I don't want random people approaching us, squealing at Harington and trying to touch him. I am of course happy for him to meet calm and sensible people who ask first so I can use it as a training opportunity. When we find these people, it's a breath of fresh air. I've noticed that there also seems to be a big assumption that because a dog is perceived as as ‘cute’, it must be friendly. I do wonder if we would have these problems if I had a dog that wasn't a ‘floppy eared fluff-ball’.