I don't know who you are but chances are they saw you as a guillible sucker. That price is completely unrepresentative for Greece. Two beds and an umbrella for a day range in the 5-10 euro a day and I'm vacationing in Greece since 15 years now so I know. If you know where to look you can find "free" beds and umbrella provided you consume something from the beach bar, starting with 2 euro for a coffee. I'd get like a 5 euro frappe and give 2 euro off record to the lady who hands the tickets and that's it. For a few hours it's enough given that I don't lay the whole day in one place.