It's a hell of a lot easier to skin a dead animal than a live one. These allegations and videos even have been circulating forever and PETA and others basically accuse every designer of participating in such activities. Whether it's true or not, I doubt it. But I also doubt that it has never happened, KWIM?
Now if it makes you a hypocrite, depends on who you ask. Some people are against all animal by products. Some people think leather use is OK since the rest of the animal went to something else. The carcasses from the fur trade are also used too, so that's kind of a moot argument in my opinion. I say live and let live.