For yet another take on the subject - eating dog meat in the Philippines. Disclaimer - I do not pretend to have any knowledge about Korean practices, or even Filipino restaurants in the US.
Dog meat is not, and will never be, on the menu of any restaurant in Manila or any of the other cities. People who eat dog meat usually come from the lower classes, and regularly eating dog, or "asocena" (the Tagalog for "dog" is "aso") is usually a mark of being a "kanto boy" (literally, "corner boy") - i.e. one of the town drunks.
No store, restaurant, or other establishment will sell dog meat. Not even if you ask nicely.
Indeed, the only way to actually get to eat dog, nowadays, is to kill, clean, and cook the canine yourself. Killing and eating dog meat is done by people who are too poor to afford decent meat. Dogs killed for this purpose are usually strays (there are almost no pounds or animal shelters in the Philippines, except those for rare and endangered species). Of course, drunken (sometimes fatal) fights have broken out over a neighbor killing and eating the family pet.
I admit I have eaten dog meat once or twice, just to see what it tastes like. It's a bit like mutton, but more gelatinous.
Some Ifugao tribes also traditionally eat dog meat, and are the only people allowed to legally butcher and consume canine meat, due to respect for tribal and religious customs. It is technically illegal everywhere else, but is in practice often overlooked and not prosecuted by local authorities.
There were several ads taken out by a high-profile British animal-rights group lately in several local newspapers blaring the message that "eating dog meat is illegal" and that perpetrators could spend up to 5 years in jail for it. This was generally ridiculed by many, since a) nobody would ever think of turning in a neighbor for such a small offense as eating a stray dog, and b) foreign animal-rights organizations would be better served spending money to try to save the thousands of endangered species in our rainforests rather than dissuading people from eating Canis Familiaris.
I don't think eating dog meat is actually "traditional" or "mainstream" in most of this country - it's just something that poor people do. If you didn't have any other meat available, you'd eat dogs too.
thunk : most people I know who eat dog also subsist mainly on rice and vegetables, and rarely have enough money for a tin of sardines or more expensive meat. I don't think "efficient" food is foremost in their minds.