from what i can make out, looking at spanish language sites, it is a commonly used expletive term. and is commonly directed at men, but is not an insult to the recipient themselves, more the female relative of the recipient.
concha (lit. 'shell') 1. [f] [15] the vulva, the vagina (widely known and used by both sexes, however a taboo); 2. la concha de la lora [interj] fixed phrase ('the vulva of the (female) parrot') a common swearing interjection; 3. la concha de tu madre [interj] fixed phrase ('your mother's vulva') a common insult, also la concha de tu hermana ('your sister's vulva') or any female relative's vulva; another common form is la concha tuya ('your vulva'). These expressions are also used for men.
and you're right, under normal circumstances, we wouldn't really make anything of it. it's just part of the game as it is today. however, whichever way you translate it, it still qualifies as abusive language under the fa guidelines.
and what many of us liverpool supporters still find galling is that evra can make so many violations of the rules in ONE game and go unpunished, and suarez can respond to him with 1 comment, which is not necessarily abusive, and get dumped on from all quarters.
as for the pfa, fa, eufa, fifa. they all useless incompetent, corrupt institutions. i'd like to see all clubs bypass them completely and form their own governance framework where they can form their own consensus and run things for the equal benefit of all clubs, not the benefit of the people running the governing bodies.
You're (deliberately?) missing the point here - why would a Frenchman utter an 'exclaimation' in Spanish? The FA try to make out it's like he caught his finger in the car door or banged his toe getting out of the shower. As I e-mailed Martin Samuel (and got not response) if I, a Scouser of Chinese descent living in Yorkshire, went up to David Bernstein or him and screamed at him in Hebrew "Your sister's c+nt!" would you at least not see it as a calculated insult, almost certainly racist in design, or would you think it was just a reflex 'exclaimation' that I hadn't given much thought too?