They are not just fun, but also just a great way to socialize and make some new friends or just some acquaintances. Plus, having drinks while you're in the pool is an experience on its own.
I know not everyone knows how to paddleboard, but I assure you I'm not a pro either. I can barely stand up. It's a fun, safe, and very laid-back activity to try especially during hotter temperatures.
You might not have access to this depending on where you are, but if you do end up going somewhere like Hawaii. Do book this activity. It's worth the money and you will see a lot of cool marine life.
This might seem super simple, but it is still a good activity. Sometimes we forget that we live in close proximity to the beach and don't even end up taking advantage of it. Work on that tan.
If you live in a colder climate, you know how it feels amazing to play any sports outdoors. In NYC, I love playing tennis at Hudson River Park and it's completely free. It's first come first serve.
You might not be the road trip person, but I advise you to reconsider. it's fun to drive somewhere along the scenic route for a few hours with your windows down and enjoy the breeze.