"C'est un ami de l'église. Il est Gallois."
"Gallois ? Eh, beh, F*** off !"
I didn't think the guy deliberately intended to be as offensive as that. Sometimes people learn those words from American films and they don't realise how rude they are. A bit like me when I described a trombone player as "pas le petit Yamaha, le gros Conn" and made people erupt in fits of laughter.
I thought "Do I reply in the style of Sarkozy - gives as good as you get ? Do I laugh ?" When you don't know what to do, there's always the option of doing nothing...
So I ignored the remark and said hello. He repeated it. I ignored it again.
A little later he said "Were you shocked when I said that ?" and I was able to explain that that's very very rude indeed and one certainly doesn't say things like that in polite company and certainly not on first greeting someone unless one is aiming to provoke a fight, and if he was I'd take him on any time, big as he was.
(OK I made that last bit up...)