We joined a private club 3 years ago and while I agree that it can be expensive, and out of some people's budget range, if you can afford it and love to play golf, I would recommend it.
Here are the main benefits that we've seen:
1. Ability to make great friendships
2. Easier access to tee-times
3. Ability to play faster
4. Opportunity to play more often
5. Better practice facilities/equipment (balls) than most