Assuming the aesthetic and utilitarian principles were upheld, I wouldn't have a problem with a living or semi-living jacket, much less a dead leather jacket that was grown that way.
If it's alive, though, I'd want some assurances that it wouldn't eat me and wouldn't get sick and start erupting fluids on me or whatnot. I'm pretty sure that by the time it got to me, though, it would be killed, tanned, scotchguarded, and giving a nice warm lining, so no, I don't care that it didn't come from a cow. (I suspect cow leather will be cheaper, though.)
Frankly I'm surprised that they're growing it in jacket form-- it should be easier to grow sheet-leather in vat or something, the way I see it. Is there that much need for a seamless jacket?
BTW, I recall hearing part of The Space Merchants on NPR, part of "2000-X," which was a year-long series of radio plays based on vintage sci-fi. All I recall abotu it was that a food company wanted to package its baby formulas in a particular red packaging to condition the children to love its food, which as they grew up would be in the same colored packaging.