Even now there are still simpletons who don't understand the reasoning of those deciding to stay away of these sites. I'm saying just understanding it, not necessarily agreeing to it.
I don't get why it's necessary to justify not using such a "tool".
That was my experience a year or two ago. At some point I deleted my facebook account, because the value I got out of it wasn't sufficient to tolerate all those annoyances: changing email notifications, constantly changing privacy settings and policies, annoying ads, annoying messages from people I barely know...
Mind you, the constantly shifting privacy settings are weird, its easy to be really granular (go to your Activity Log) but it is effort. You can also change privacy on a post by post basis, but its sticky, so you need to be careful. The ads never really bothered me (except for the dating ones just after i came out of a long term relationship). In fact, I never ad-blocked facebook because I could x out of ads I didn't want to see. The annoying messages from people is not really Facebook's fault, though I feel your pain....
Making someone into an outcast because they do not use your favorite social networking system is the problem here.