In order for the protection to be somewhat adequate, you would need a large and dangerous dog - but we all know that dogs can wander off, be stolen or poisoned, so HW around a dog's neck does not look smart at all
I agree that it would be bad for privacy, unless the logo was on the underside (in case it's a bracelet) - but it's hard for any company to put their product on the market without it being clearly marked with their logo.
Maybe they are targeting a younger audience? A lot of things don't make sense to me today and I wouldn't buy various things, but the companies that sell such products make huge money, which means that someone still buys them. What I know for sure is that every company simply has to release a new product from time to time in order to stay in the race with the competition.