My daily kicks are typically natural materials. When I was younger, my go-tos were Fluevogs. Docs, and some vintage boots, heels, etc. I also had the most comfortable pair of hiking boots ever. Plus I had some knee-high fashion mocs. These days I have been favoring Vans.
On the sand, Vans work but they can make walking hard. If you have an aqua shoe, go for it. Otherwise, I would steer toward nuks, huaraches, and sandals (flip-flops) if there are rocks or sketchy sand. Huaraches saved my feet in Chiapas so they are a no joke great buy–especially once you break them in. For sandals, you can look to Rainbow, Reef, or Olukai. I have a pair of Clarks I wear to pools and they have done okay. If you have a lot of walking to do, make sure they fit well. That means your foot stays on the bed of the sandal and the tong or strap fits nicely without pain or chaffing. You might as well buy a pair for a dollar if you are down for whatever.
Note–in Hawaii, sandal (slipper) theft is pretty common, but not really talked about because most tourists wear cheap flip flops and no one wants them. If you wear a name-brand, guard them. You can always take the cheapies to the beach and wear the nice slippers out.
If you sail, you need grip. For style, the best nauti shoe is Keds. Sperry makes a great “boat” shoe but make sure they have traction on the bottom–otherwise you can slide right off the deck. Seriously. The key to a deck shoe is traction and water resistance or quick dry. After that, make sure they are comfy.
I don’t have a lot of experience with Chucks at the beach. The canvas chafes me a bit in the heel so I don’t currently own a pair but I would go for the low-cut pinks.
Below is an example of a look I would wear to the beach for surf, sail, or just to chill. The model is wearing Keds.