Linkedin is a terrible company, I've always resisted making a profile there because I think that to support a company like that in name is to give them a free pass on their despicable behavior. No matter though, I still receive their spam on a daily basis, but that's nothing a filter rule can't take care of.
After quitting my full-time job and going independent(ish, for now) last year, I've sometimes regretted deleting my LinkedIn profile, as it's so commonly used for networking and searching for leads for job candidates. But I agree with you that it's a terrible, and it's why I deleted my profile. I didn't even know how creepy/skeevy their business model is then, but what I did see was that their product is just BAD in…
I really don't understand what value regular users are getting (let alone people paying for Premium). Part of me believes people will realize this and delete accounts en masse, but then I remember how status obsessed everyone is and I have my doubts. LinkedIn is sort of like Zynga for career status, so I suspect there is a lot of user psychology they can manipulate.