Beach beds

In August we visited ayia thekla beach and wanted to rent just an umbrella ie not umbrella and two beds. And the employee said the minimum is one umbrella and one bed. On another occasion years ago at makronissos beach that was very possible and now I find that very inconvenient and questioned the employee 's intentions but did not complain. However i want you to confirm if they are allowed to demand me to pay for minimum one umbrella and one bed when the prices are displayed per item!!