Assuming a "lounge" was designed and created that was not just an adult-only "watering hole," I'd be in favor of having them strategically located around the parks. There are days, I'd almost be willing to pay for a little bit of quiet, air conditioning, and a place to take a short nap! There are only a few eating places in the parks that are relatively quiet so there are not a whole lot of places to avoid the normal crowd ruckus for a brief respit.
While I love the parks, the almost constant din of background music, crowd noise, etc., makes me long for a few minutes of quiet. When my daughter was little, I'd have paid real money for a quiet zone so she could have taken a nap for a little while rather than the baby buggy naps which were always interrupted every few minutes by a noisy passerby.
As I age a bit more and still push 18 hour days for 10 days or so a year at WDW, I'm beginning to enjoy "sit'n down a spell and take'n a load of my feet." A quiet zone might be a nice touch to savor the flavor of the day.