Why don't they make playgrounds for adults?

Because playgrounds are funded by tax dollars (paid by the adults), because people are convinced (probably rightly so) that children need them. Meanwhile, adults are willing to shell over $$$ for amusement parks and other playgrounds. read more

Meanwhile, adults are willing to shell over $$$ for amusement parks and other playgrounds. They do have playgrounds - it's just that they cost money. Because if they didn't - taxpayers are going to fund them, and it would be hard to convince taxpayers to fund playgrounds for adults. read more

Actually, there are a ton of adult-sized playgrounds here in China. Elderly people use the equipment to exercise and socialize. You can find these "playgrounds" hidden in residential areas, parks, amusement parks, and zoos. read more