The chair guys come around to the individual chairs to collect your money, unless you are on the multi-day pass and even then, they come around to the individual chairs to collect your chit from your book and they put the tag on your chair each day. I'm not sure right now where they sell the multi-day pass, that may be at watersports, but I thought it was at the store. Chairs are not reserved at Club O by putting down towels. If you are talking about people who are staying at Club O putting down Club O towels to reserve chairs for you, they only give out one towel per person, so your friends will not have any extra Club O towels to put down on chairs, even if they wanted to. Regardless, chairs at Club O are reserved only by either a daily tag or the tags which those staying there are given for the duration of their stay. I would not count on any chair being reserved just with a towel on it. Regardless, unless you have to have a chair in the front row, I don't really think you'll have that much of a problem getting a chair on the beach.
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