What is beyond the pale, exactly? Is WWII beyond the pale? The Holocaust? Vietnam? The Troubles? Vietnam? First Gulf War? Second Gulf War? 9/11?
If the vast, mechanised slaughter of WWI is considered a reasonable hook - on which to sell your Paxo, crates of Carling and onesies - then what is unreasonable?
Is it the passage of time that makes a vicious, brutal, cruel war appropriate source material to advertise a greengrocer? Or is it something about the way we romanticise wars, as if millions or people being cut up into little bits by hot metal or gassed like rabbits is merely to be used as the set-up to the latest warsploitation novel?
What if this advert was for Nescafe, Go Compare or Toys R Us? Where does that notional bad-taste barrier reside? Over 15m people died in WW1; a relatively miniscule 2,606 perished when the Twin Towers were struck. Would we base an advert around that? What about a Jewish member of a concentration camp giving another a scarf while shivering in the snow? Too soon?
The get-out-of-jail card in this instance is the British Legion's blessing and a charity element, but fundamentally this remains an advert. It only exists because Sainsbury's wants you to do your Christmas shopping with them, as opposed to Tesco, Morrison's, Asda or - God forbid - Lidl or Aldi. That's what the function of those people - those real people who took part in this actual event, most of whom probably died violent, pathetic deaths before the end of the war - amounts to in this advert.
The Christmas Truce remains a poignant flicker of humanity amid unimaginable barbarity and suffering. 100 years later it is being leveraged to sell more Sainsbury's Taste The Difference Mince Pies to a misty-eyed audience waiting for the next segment of X-Factor. Shameful.