Last year I was working full time in a high end furniture showroom that sells only to the architect and Interior design trade in New York City. Besides furniture and various objet-d'art, we offered the option of a pretty good selection of fabrics and leather for upholstering any chairs, ottomans or sofas that they might purchase for their clients. The designer generally likes to use their own fabrics that they have purchased from another vendor, that is called COM or COL in the case of leather, but sometimes it is just alot easier to do a little one-stop shopping and depending on the fabric, it might even be a better deal.
One day, I was working with one of my more pleasant clients (which was rare). We talked about a piece of upholstery that she had wanted to purchase and I offered to show her our leather collection. She asked if we had any "faux" leather to which I responded that one of the lines that we represented did indeed have a pretty good selection of faux leather - quite realistic looking. I thought that she had inquired about the faux leather because she was trying to keep within a certain budget, but she looked at me and said: "after all, why kill the cow"? I sure wish everyone thought like that..
I will say that I am a big animal person and will likely never offer my clients the option of fur (only faux). I am, and have been a rabidly (no pun intended) anti-fur person for most of my life, so I really feel that if someone absolutely must have something made with fur then I am not the designer for them. On the other hand, why kill the cow too? There are plenty of great faux options out there nowadays and many benefits to using it as well. Yes, some of us still eat meat, wear leather shoes, gloves, coats, have leather sofas, easy chairs and leather upholstery in our cars, but if it really isn't necessary, why indeed kill the cow?