westerns as crime fiction in a historical setting

I'm familiar with the idea that westerns are just "crime fiction in a historical setting" (a comment left on my DSD post and one I've heard before). It's true, but only partially and to an extent. A lot of the westerns in the 50s and 60s for example were hardboiled westerns that fits the above idea but there is much more to the genre, and other modes and story types are available. My current opinion is that picaresque westerns serve the genre best for example.