We didn't 'bunt' but did have subtle solar lanterns up which seemed to start a trend... by the time we left at least two other tents which had been sans lights, had also paid and displayed. And we saw bunting on Dutch tents a couple of years ago, complete with wind charms and other decorations. It's not exactly hurting anyone and, if it pleases you and isn't offensive or creating a noise or danger or obstacle, then GFI. If they think you're mad, so what. I like the suggestion of a 'courtesy tricolore' tho.
Last year in southern France there were loads of pitches with various types of solar lights, tealights in lanterns, tablecloths and plants in pots (usually geraniums). We had all three of the above, but not bunting, but I don't see any problem at all in using that. We bought our tablecloth (wipeable) at the local French market. In fact, we liked it so much we bought two different ones. It was much cheaper than in the shops around here.
Just to add, no windbreaks, though, at all. Everyone spoke to everyone else, even if it was just to say "bonjour" or "bonsoir".
------------- Pauline
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