Canesten used to be sold on supermarket shelves, Sqad, but it suddenly disappeared and was only available from pharmacies. When I tried to buy some for jock itch a few years back, the pharmacist said that he couldn't sell it to me because I was over 60 and that he couldn't offer any alternative without a doctor's prescription.
This quote is taken from a relevant thread on the HealthUnlocked website. (I can't provide a direct link, as you need to be logged into the site to access its content):
"Unfortunately working in pharmacy we get this all the time, no one in any shop not just in a pharmacy's. We are not allowed to sell anyone over 60 or under 16 any Canesten products, as it is not licensed for those age groups. When you are over 60 you can get something called Atrophic vaginitis which mimics thrush it happens to postmenopausal women who's lack of oestrogen reduces vaginal resistance to infection and injury, which can produce similar burning and itching symptoms to thrush, but thrush is uncommon in postmenstrual women. Therefore we can not sell it because it could not be thrush at all"
(Yes, I know that doesn't really explain why it can't be sold to men but it appears that the ban on sales to over-60s is a blanket rule, irrespective of gender).