at most large dailies, photographers are often given a choice between canon or nikon. you won't see much in the way of rf because they're not the most practical camera for newspaper use. of course, if they so choose, they can shoot with whatever they want...as long as they produce work that can be used.
me ? holgas, leicas, Franken-panorama Nikon F2, 4x5 and even pinhole. daily beaters=D3's and a stash of Nikon's best glass. professional to me does imply, in part, that I can work the crap out of it and it'll still keep ticking.
Unfortunately, Holga doesn't have pro service or loaners yet 😉