I am a big fan of the .25 cal cartridges. Although, I tend towards the 25-06 over the .257 Roberts for the bump in speed.
But, I think the OP makes a good point that, as nice as the .257 Roberts is, it is not the best "utility" round for those living in the West. That doesn't mean the .257 Roberts doesn't perform well in its respective niche, which it does quite well. But being good in a niche application, is not the same as being a good utility round. Meaning, if you like utility cartridges, the .257 Roberts doesn't make much sense. If you like low recoil and nostalgia and only shoot whitetails/antelope/etc. at moderate ranges, the .257 Roberts makes a lot of sense.
I would also say, that since we can easily and cheaply buy meat at the grocery store, hunting is about fun, and if a person likes a certain round for other than performance reasons (nostalgia, tradition, history, got a good deal, etc.), then they should by all means hunt with it and enjoy themselves.
(As an aside, taking dangerous game off the table, the best utility round is the 7mm-08. This is particularly true with modern monolithic bullets, which don't wastefully shed (i.e., any weight lost is in the form of sharp shards that continue to do damage after separating from the bullet shank) close to half their weight shortly after impact.)
