These terms are typically boiler plate contracts that lawyers put together, often ones who are not specialist in copyright law. About a year ago, photographers went crazy over the same thing with Houzz's terms. The rumor went around that Houzz was selling images that photographers (or whom ever) posted to stores, like Lowes, for ad use. The ASMP looked into this and was not able to find one instance of a photographer's work being sold through Houzz. They also sat down with Houzz and talked out the T&Cs and the issue of selling images. Houzz said that they have never had any interest in doing so, however they could not (just like any photographer who has a website) prevent people from stealing the images through right click downloads or screen shots. They do use images in feature articles where items and finishes in those images have links to stores, like Lowes, where consumers can buy the same item. This may leave a bad taste in your mouth, but I can not think of a better way to get in front of residential designers, not to mention it is free.
I feel this is a little of the same thing. (LinkedIn makes it money differently and does not do anything with the images other then allow users of the site to see them.) I use LinkedIn all the time and have gotten work from people seeing my profile whom I did not know previously. And this was good paying work, not "hey, I have $100, can you take 50 shots of a project for me?" Not to mention I am connected to a large number of architects, designers, and marketers in NYC and Philadelphia, which means I am connected to virtually anyone in the design industry in those cities through someone I know. Makes it very easy to ask for referrals, and we all know referrals are the best source of new work. It is a great site, so long as you actually use it; creating a profile and then letting it be is not using it.
You may disagree with me and for the time being you will be right. Most of all the decision makers are in there 40s and 50s and more old school in finding photographers. But once the current 20 year olds move into those decision making positions, you better be on social media.