I went to windells last year when i was 19, i went with my little brother, had the same thoughts as you thought i was too old for sure. But Anyone over 18 gets throw in the adult house across the street, and it's a time and a half there's a hottub, pool table, and bonfire pit.
The house has it's own van and there's a "counsellor" who takes you guys into town for supper every night, and takes you to the grocery stores for booze and food etc. One night is sushi night in portland, another night everyone goes down to the skyway bar for a night out.
Adults get a private session in BOB every night at 10pm when there's no little kids running around.
