What I remember reading (maybe in a Straight Dope column?) is that Mel Blanc didn’t like carrots, not that he was allergic to them. Apparently no way was found to produce Bugs Bunny’s carrot-crunching sound other than to actually chomp on a carrot, which was unpleasant for Mel. Had he been allergic, I doubt he could have done it.
We covered Mel Blanc’s dislike of carrots in an earlier thread. As Gary T. says, he wasn’t allergic. But he did have to go through a couple dozen or so carrots per recording session, so he kept a trash can nearby to spit them into after chewing them.
As far as the Rolls Royce question, about 20 years ago that would have been Antelope, Oregon. But ole Rajneesh has moved on and I think they liquidated his collection of Rolls (he had 92 at one point).
I read (here, I believe) that a ‘kiss’ is a candy making term for a small piece of chocolate, and that’s where the Hershey’s Kisses got their name.