I agree - a program will ask for board scores for all applicants, or for none.
However, realistically the programs can guess/ballpark your board scores by the internal medicine residency that you are in (particularly if you are a US grad). In other words, if an applicant is from Harvard or Johns Hopkins IM program, one can assume the person did well in med school and had high USMLE scores also (definitely above average).
Some cardiology programs do not require that you even send them USMLE scores, because they don't care about them much. I think that a lot of these types of programs would not have people with lower board scores even in their pile of people to possibly interview, so they just don't think it's even important to look at board scores. My opinion is that these programs probably have so many applicants with board scores of 225+, they don't even have a need to try to use board scores to differentiate between applicants. At these programs, the low-board-score types would be filtered out by other initial screening (they won't be at a residency program from which that program takes its interviewees, they probably don't have any publications, and their LOR's are probably not that great).
However, there are programs that do look at board scores. In my experience, this group included some medium-competitive type places and even some less competitive ones. I think some of these programs know that there are "diamonds in the rough", so to speak, particularly among FMG and IMG's. I think one of the ways they look for these is to look for the people with the high board scores. I don't have proof of that, but the fact that some program directors even look at board scores suggests this. I found that PD's at a couple of programs I applied to were FMG's themselves did use the board scores, probably for this reason. We all know there are some very smart FMG's at some little-known IM programs, whereas a lot of US grads at those type programs are there because they weren't competitive for the more prominent or cushy IM programs (grade-wise and USMLE-wise).
I think board scores are just one of those things that you should use to your advantage, if you have good ones. If you don't, then maybe look at programs that don't care about your USMLE scores, and if you have other good things in your application that may balance things out. There are places that would care more how many publications you have, or who your LOR's are from...