And where I would consider that tough shit and a bad business decision...
I personally hate Facebook with a bitter passion, but I don't think I can agree with you there. My other half runs her own business and Facebook / Whatsapp is her main means of advertising her services. It makes sense... that's where her customers are, and where people can quickly and easily communicate about her business. As for over-reliance on one business / service, when you're self-employed or a one-person business, redundancy in these things is something you often can't afford. It simply costs too much in time and / or money to maintain two of every kind of service you're dependant on.