NM going to a light with a jb recessed in the siding is still in the interior. NM going to a surface mounted disco is considered outdoors. If you believe that nm is not allowed in conduit on the surface of the building then why would this be any different.
I think inspectors, at least around here, see it as an okay install-- I am not sure the 08 agrees.
Because it is treated differently. Take a look at 2008 300.9, it applies only to raceways, not enclosures.
If we say the inside of a disconnect switch is a wet location then you can not install any fuses in that disconnect as there are no wet location fuses.