This was a good painting spot, because there happened to be a thicket of blackberry bushes within arm's reach to my right. Free fruit.
Of course, it also happened to be on a footpath which got more traffic than I expected, which led to some akward dances around the easel, but it could have been worse; read this Telegraph article to see what can befall an RA in the middle of London.
Even as a landscape painter I sometimes get an audience. The good thing is that onlookers soon realize that painting isn't interesting, and they drift away. Sometimes a troll will try to spoil your concentration by talking to you, but I've perfected the deadpan monosyllabic reply and cheerful countenance that makes them realize they're onto a non starter, and they soon leave in search of fresh prey.
People who do that were the bane of Cezanne's life, or so my reading about him would suggest. A sensitive man who was quick to anger, he was probably easy entertainment for bored peasants on a slow farming day. I've been leafing through the local library's copy of Cezanne: His life and works in 500 images, by Susie Hodge (available at a surprisingly high price on Amazon).
Anyway...where was I, and what's my point? Pick painting spots with free fruit, avoid those with bored peasants and/ or jobsworths.