1. Some of the Information People Post Is Actually Valuable: Most of it istn't, but a lot of people use Facebook to discuss news, politics, and pop culture. So, if you quite, you either fall behind on it, or have to seek it out yourself.
2. When You're Not on Facebook, You're More Mysterious: As in, people can't reach for their phone and check out bikini photots as soon as they meet you.
Although, you're also more mysterious to potential employers, which isn't good. These days, a lot of hiring managers assum you're old, crazy, or hiding something if you're not on Facebook.
3. Not Everyone Knows When You're Birthday Is: So, when someone says, "happy birthday," it actually means something....because it's not just an old high school friend who happened to see a birthday alert.