I agree. There tends to be a "regression to the mean" between two vastly disparate scores. A lot of it depends on the perceived senority/beer cred of one judge relative to the other. For example, a recognized BJCP judge with more brewing experience and lots of medals in previous comps might still be able to sway a certified BJCP judge with less experience. A lot of it is dependent on the personality of the judge. Some judges, frankly, are rudely dismissive of opinions other than their own, rather than being open-minded and engaged in educational discussion with their fellow judge(s). I don't find it fun to judge with them.
I've been on both sides of the situation (i.e., judging beers, and having my beers judged by others). Yes, it is rather subjective, although following the guidelines seems to help inject some objectivity to the evaluation. The problem is that not everyone can detect or appreciate every aroma, flavor, flaw mentioned, nor give the same relative weight when judging. To be fair, the judges don't have your recipe sheet nor were they with you during the brew process. We're going off of your entry #101 being labelled as a "Pale Ale" or whatever. We're strictly going off the BJCP guidelines and our senses.
I also occasionally encounter those who just won't give a score higher than 41 or 42, even if it is really good, because they perceive that a score higher than that just doesn't get awarded, and, if it does, then it pretty much guarantees that the beer they've awarded a score of 41+ is going to win the comp. This is more of an issue during intra-club comps with just one round, and some judges may have entered a beer as well--in other words, they have "skin in the game." Even though they aren't judging their own entry, they're still judging in that style--something that wouldn't happen in a real BJCP competition.
I sympathize with you; it is frustrating to have beers judged by those with little experience and/or no BJCP certification saying giving a lower than expected score and very little in the way of constructive feedback, and then getting a vastly different score at a different competition (along with a medal). I'd suggest having your beers judged outside the homebrew club at one or two competitions by those who have no "skin in the game" before you make any conclusions about your beer. JMO.