I'm also confused as to why English-speaking people in general, at least in the U.S. and Britain, are fine with eating sheep but not goat. Goat is one of those exotic meats the foreigners eat for some reason. I've never even had the opportunity to try goat. Could it be all that different?
Goat is a bit of an acquired taste. That's why it's usually heavily spiced and stewed or slow cooked. And it's not like people eat a ton of mutton, either.
Coming to think about it, really don't know why lamb is not common here. Maybe it is some availability issue... I really don't have much idea about this but was wondering lamb/sheep have any problems surviving hot weather.