People will always be able to refuse giving any I think. Last year I bought a birthday cake where I was asked a Facebook id to message me, then since I have none, a WhatsApp id, then a twitter id if I remember correctly, then a phone number (it is voip and didn't set up calls). In the end she agreed to send an email and since I use simplelogin no private email leaked.

That being said I am waiting with impatience the day when a Nigerian bank will refuse a loan because of a picture on Facebook showing disadvantageous situations.