>>2342604German alpine leather shorts were in fact working trousers until the early 19th century. They were afterwards replaced by wool trousers. A bavarian teacher decided to revive them because he considered them some kind of original heritage, an idea which the bavarian king and later the nazis were happy to adopt. For a while they were very popular for boys, until they were replaced by jeans in the 60s.
IMO leather shorts make more sense than trousers outdoors because they are inherently more breathable. Warmth can be increased by wearing long socks (also part of the alpine style). But unless you're sitting on rough ground or working a lot, you don't really need their durability, which is the only advantage of leather.
