Well that's the thing, other than word of mouth, there isn't a great way for applicants to know what placed have high perceived prestige. Sure, there will be people that go to MGH or Stanford because of a general public prestige. But within the field, perceived prestige is different than in, let's say, internal medicine, where the expected institutions are prestigious (Harvard, Hopkins, UCSF, etc). County hospitals that no one outside of medicine, or even in medicine, have ever heard of (i.e Hennepin, Denver Health, Cincinatti) have more perceived prestige in EM than in other fields. So in that sense, I do think applicants look at this and get a sense of which programs have that perceived prestige you mention.
Is it anyone's deciding factor? maybe. probably not. Is it in the minds of many type-A competitive med students as they make their rank list? I don't think we need a source to answer that question.