I shouldn't think this would be a regular occurance. I travel there regularly to visit the fishmonger, baker, butcher and chemist; I have never seen anything similar. I don't live in the immediate vicinity. I live south of Nunhead cemetary and north of Camberwell new cemetary, a very peaceful area (no pun intended) handy for the park, lots of friendly neighbours and big victorian houses. Commuting options from Nunhead, Brockley or Peckham Rye.