Is that just because you're a community-oriented program, not a research program? I'm assuming that because I am a strong research candidate, a program that I don't have a geographical link to but make a strong case for my research interest in (Stanford is a good example of this) would be more inclined to invite me for an interview. I can't imagine why having spent a month at Stanford would necessarily help me out at UCSF or UCLA, although I have heard this argument before - "prove that you have an interest in that geographical region with an away rotation." Okay, I guess so?
I mean I'm well aware of the importance of networking, reaching out to PDs, having my advisor reach out if necessary. I'm also well aware of research fit as a concept, and doing my homework and selling my research compatibility with a program in my personal statement. This is how I got into grad school in the first place and frankly, research fit is my main motivator anyway. Given all that I'd be surprised if a PD at a program looked at my personal statement where I make the case that I'm a strong research fit and said "eh but you've never lived in Southern California / Portland / Texas / wherever so therefore you could not possibly be interested in our program bye." An away seems like a good thing to do if I'm in love with ONE place, but right now I don't have one top choice.
I know the cost of an away pales in comparison to med school and application costs, but I'm not in debt and I've lived on a stipend for 8 years. It really is a factor for me.