I think a private membership decision has more to do with where you live and your lifestyle as they both correlate directly with the economic side of the decision.
I'm 36, started playing junior golf on a private course at 10 years old. My dad moved us into this exclusive neighborhood in 1988 that was brand spanking new. Initiation cost was $15K plus monthly dues and food minimum. At the time, it was great, 3 kids playing golf and both parents. Also had swim/tennis though you could opt for only the swim/tennis fee. Guest play rates were ridiculous.
Fast forward to today, the course is still very nice, but my Dad has quit and rejoined the course several times. There's now no initiation fee, dues are relatively reasonable now, but there's still a monthly $250 food cost. However, instead of just a CC, the HOA built their own Swim/Tennis facility so you can join that and not even have to join the CC swim/tennis. Weird but nice.
There's now a few private courses very close by and a public course that I live next to that is very nice,
http://www.cobblestonegolf.com/
I pay for a Cobb County Card at $100 for the year and get $20 knocked of the $65 rate each round. Which $65 is expensive in this area where you can find deals for $35-$45 if you're willing to drive more than 10 miles.
Now, a company called Canongate which is now
http://www.clubcorpatlanta.com/members-atlanta.html
has bought up several former private/single owner courses, so now, you buy their membership with a home course and can play the other courses. Still expensive.
Most people have to work, and they have to work M-F, 9-5 and they have families and kids with other activities outside of golf, so financially a private membership doesn't make sense if you look strictly at the numbers.
If you value the club stuff, then go for it. If you're like me and you're having to squeeze golf in, it'd be ludicrous to buy a membership, even if I lived inside the CC. I'd much rather get a steak at Ruth's Chris than the CC to meet my $250 food minimum. Just for the golf break down, it would be 5-6 rounds a month (every month including winter) to break even compared to local courses, which is actually not bad now, used to be alot more.
I'll stick to no CC/membership for now. We just have several courses now, with great deals, compared to when I grew up playing. Maybe in 8 years when my kids are old enough, and into golf enough to bleed me dry, I'll think about a membership.
To each their own, but I'd definitely trial for a year no strings attached and read the quit/sell policy. I know for my dad's $15K policy they would only allow one sell for every new member, so basically it was worthless by then. But he is a member again :)