Ken's! Truthfully one of my favorite restaurants in the world. Last time I was in Hawaii I think I went almost every day.
...And no one wears clothes in Hilo.
It is a great restaurant! I've been there three times now (since its in walking distance from my hotel). Its like a Dennys (open 24 hours) only with good food and a ridiculously large menu. Theres like 250 different items!
Also I haven't seen nudists in Hilo yet but in Maui some friends I met up with and I interrupted a shower in a waterfall, and them when I was ocean kayaking I saw some dude playing nude frisbee with his dog on the beach.
And just a few minutes ago I accidentally flashed my hotel neighbors when I walked outside in a towel to check if my swim trunks were dry and the wind blew my towel off
The plus side to that was when reaching to retrieve it I found one of those awesome tiny little frogs that make insanely loud noise at night! They're like the size of a dime!
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No but I don't have any problem with people who chose to live their lives exactly how they want to.
I've actually never understood the issue with nudity. People make the human body out to be a dirty thing even though we all have one if we're still alive.