He knows them only by their dogs. They know him not at all
A man walks through a park where his dog enjoys full celebrity — 'It's Jean!' ringing out from strangers by the tennis courts — while he himself is looked up and down 'suspiciously' by Jean's own fanbase, tolerated as the entourage. His wife, on her parallel circuit, greets a dozen friends whose names she knows. He knows one man by his hobby and one dog called Max. The silhouettes wave at her.
The park itself is going the same way as its visitors: festival season has arrived, and with it the temporary walls, bisecting the fields, blocking the familiar paths, herding everyone the long way round the outside. 'Like a prison exercise yard,' says a woman his wife knows and he doesn't. The commons, enclosed for paying customers, most of the summer, every summer now.
His defence — that he has his OWN park, with his OWN friends, whose names he doesn't know either — collapses in real time, mid-conversation, as such defences do.
Reputation here is built on 'a thousand daily encounters', and he has attended none of them. It's the mornings, you see. There is a version of your life happening without you, and it starts at 8am, and the dog is in it. As expected.