bare foot cheek

With the sudden outbreak of sunshine I decided it was time to invest in a pair of sandals.
Visiting a couple of shops in the city centre I watched various women trying on shoes and sandals - all with bare feet.
Surely it is unhygienic for people who have been tramping round the city centre in the heat to then put their sweaty feet into shoes which other people may buy?
I would have thought shop assistants would insist that people only try on shoes when wearing something on their feet.