Also, I don't care about what they say. If you don't have a thick skin and the capacity to shake off random comments from strangers, you won't do something unusual that attracts that kind of attention for > 10 years
If you don't have a thick skin, you also probably wouldn't be running barefoot.
(sorry, my androgen-induced aggression got the better of me)
For example, the snow and ice melted here yesterday, exposing gravel on asphalt which is borderline painful to run on directly. Also, e.g. very cold winter days or just nasty gravel roads may inflict varying degrees of pain.
Otherwise, it can also be slightly painful for the soles during later parts of long runs, especially when inexperienced or when running for the first time in months.