Stable Diet?

You meat-eaters are a funny lot. No problem eating cows, sheep, chicken or pigs but when it comes to chowing down on a bit of horse flesh everyone goes mad.
Horse meat has been found in beefburgers on sale in UK and Irish Republic supermarkets and quicker than you can say Hi Ho Silver away, they are whisking them of the shelves amidst a consumer outrage, Peta says the thought of tucking into a horse burger has shocked the nation.  
So why is it certain animals are fair game for the middle shelf of the cooker and some aren't and is it a British thing because horses are commonly served up in other European countries.
It can't be the argument that we are a nation of animal lovers, if that was the case then we wouldn't be shovelling all the other animal down our gullets and it isn't because horses are cute and we don't want to think of cute animals receiving the stun gun because they aren't, or rather, not as cute as a rabbit or a lamb anyway and they are on display in all butcher shop windows. 
Maybe we have an emotional link to horses due to them being so helpful to humans down the ages where we have used them for transport, working the fields and even in the military but that isn't a uniquely British thing, all countries used them for the same things before automobiles, tanks and tractors came along. 
It isn't a hygiene thing because pigs spend the day rolling in their own filth and that doesn't stop the bacon sandwiches being eaten in there tens of thousands with a early morning cup of tea.
A horse cannot be classed as a pet apart from amongst a few, more people have rabbits in a hutch in their garden then own horses so out goes the argument that we won't eat anything that can be regarded as a pet.   
Whatever the reason, British meat-eaters draw the line at eating horse in their burgers although they have no problem with the rest of the burger which it is probably better not to know what it is made up of.