If Facebook is the only way a government entity or business chooses to communicate with the public, they won’t be communicating with me. Fortunately, our county still has an old fashioned website where I can go for info, like during hurricane season. I can receive the info I need and keep my life private.
I have to say though social media has evolved over time. I mean consider how expedient you can get a company's attention just by tweeting them. In fact a lot of people on the SWA thread talked about that being a quick way to get a response. The olden days of calling up or e-mailing a company via their "contact us" button are just further back in priority and less rely on websites unless it's their chat function (which I love using when I can). I can't fault a lot of these smaller businesses for not having a website because that can be expensive to build and maintain for the domain. Some of the ones I've seen go around to trade shows and so they have a business card but often pull mostly from FB especially. Consider etsy too which is a lot of businesses that may not have websites they just use Etsy to help them sell.
I had a question about a device I was considering ordering and I e-mailed them on their contact us, then I decided I'll just FB message them. I got a response within 4 hours of FB messaging them and 4 1/2 weeks from e-mailing them. I just ordered something and received it last weekend but didn't like the color on me even though the size fit. I read their return FAQs but it really only spoke about sizing. I decided I'll FB message them. They got back to me on the first subsequent business day and said they can do it easier on their side manually for the exchange (which 1 free exchange is allowed without having to pay shipping fees again) since it's not a size issue but just wanting a different color. They pulled up my order (somewhat creepy I might add lol so I get that part of your comment about private life) just because it matched my FB name and said "what color do you want". I message back what I wanted and they said okay we've ordered it for you here's your new order number and here's the paid postage label for your return.
I know to some that may seem annoying but the world is more instantaneous now and entities go to places where people are more likely to check frequently. It's a lot easier to update on FB or Twitter than it is to continuously update a website in this quickly changing world. I do believe in situations where there is danger like weather related places error on the side of blasting the information out to all sorts of avenues (radio, tv, push notifications on phones, e-mails, website updates, news breaking into a program, news websites updated, etc). I'm hooked up with my county's emergency alert service that they would really want people to enroll in and I get text messages when there's weather like a severe thunderstorm watch or warning and a tornado warning for example.