Really surprised by all the comments here. This seems like a solid business decision by LinkedIn, riding the line of what a user is willing to accept and balancing it well with the potential rewards.

Look at every famous company and you'll find tactics that you don't agree with, and sometimes downright illegal (Path).

If you're not willing to do desperate things, to do what is necessary for user acquisition, good luck trying to build a successful business, because pure blind luck is exactly what you'll need.

Stuff like this is what really separates successful businesses from the failures. It was never about some grand vision, or some belief in connecting the world. It was about figuring out how to acquire users, retain them, and monetize.