As a business owner, imagine that I’m just doing a research, I don’t know exact dates of my holiday (it mostly depends on your availability) and I’m not sure how long I want to stay. I need to find out the options, consider them and talk with my partner. If we would talk on the phone, you would give me dates but what’s next? I would hang up anyway to think about these dates. And that’s not closing a deal. That’s inconvenience for me, because I need to write them down anyway.
The main reason why leading world companies create accounts in social networks is to attract traffic to landing pages and websites. YouTube's video hosting by the number of search queries is second only to the Google search engine, and you can attract some of this huge traffic flow to your site / landing page by simply posting your video (and related links to your web resources) on this hosting.