Being a former conservative and modern-day "in-betweener," I have to say that your last paragraph there doesn't exactly constitute the hypocrisy you'd like it to.. (for the record, I'll say again I think Mark has probably the most logical arguments in the thread here. I don't 100% agree with him, but I definitely do to a degree, mammoth ivory issues particularly so.)
The use of the products above, in moderation, aren't on par with what could likely be the extermination of a species. When I was a boy, we raised our own chickens for eggs and eventual meat. There were always more chickens in the coop than on the table. Etc, etc.
I do agree with your last point, no one should be forced to live in a way that they do not wish merely for the sake of others. But, as some of us (Mark included, actually) feel a responsibility to elephants and other animals and the planet of which we are stewards in general. If you don't, that's alright. Others will pick up the slack.
Our resources can and should be used for our benefit, where possible, provided they are either sustainable or can be replenished. In this case, as a higher thinking life form, it is incumbent upon us, if we do make use of these resources, to both acknowledge that use and see to it that the plants and animals we use, as a species, can remain. It's pretty simple.