Even things which don't require a prescription, but which are still 'pharmacy only' items, can't be sold when no pharmacist is present. Without a pharmacist actually there, the pharmacy becomes 'just another shop'.
So, for example, you can buy several 48-tablet packs of paracetamol (without a prescription) when the pharmacist is present but you can only be sold a total of 32 tablets if the pharmacist is, say, on his/her lunch break. (i.e. the rules that then apply are the same ones that apply at a supermarket checkout).
Similarly, you can't buy antifungal creams like Clotrimazole when the pharmacist isn't there as, even if the person making the purchase is clearly under 60 years of age, the pharmacist is still responsible for checking that the person who'll actually use the cream isn't over 60.