Well there was that (at least one) episode that was rather infamous pretty strong subtext in that direction, and then someone that worked for a CN youtube channel was fired for suggesting they might actually have had history, I've seen shipping pairings built on less.
Thing about it is, GLBT people have historically had so little representation in mainstream media that they're clamouring for something, anything, so they maybe read a little more into awkward writing that's meant to communicate friendship, or shipping-baiting by some more cynical creators, or actual intentional GLBT subtext snuck in there by subversive creators that try to do whatever they can without causing the conservative media overlords bringing the hammer down.
Just a guess, but I think the reason you offended the creator was that you implied (or seemed to) that they were drawing this entirely because of bandwagon-jumping and pandering.
I don't think it's really blown out of proportion when there's a show-stopping song number that involves one character's hidden feelings being aired out in order for stolen personal treasures to be recovered and the day to be saved, seems a fairly obvious parallel to the "closet" and being in or out of it, especially when they relate to the motivation of "wanting to suck the pink out of your pretty face" (I don't remember the exact quote so yes I am paraphrasing, but it's still pretty similar) Vampiric red-fixation or not, that seems more than just confessing friendship, not to mention that one of the precious treasures retrieved by the efforts was a T-shirt given as a gift by one girl to the other that the recipient wears as pyjamas, this all seems pretty blatant to me.
To be fair, there is some bandwagon jumping and attention getting in the community, but a bandwagon has to start moving somewhere for other people to end up jumping on it, and the concept of "gaydar" isn't entirely inaccurate, as gay people tend to be more observant of that kind of subtext since they're actively looking for it, whereas (more intolerant) hetero people tend to actively go out of their way to rationalize other possible explanations.
Maybe actually watch the episode in question and decide for yourself? Then once you know where the community is coming from, you can either find common ground or respectfully agree to disagree without others getting the impression you're shitting all over the mere notion that there's something there. I believe it's called... "Something Missing" Or something to that effect.
Mm, and there's nothing wrong with it being up to interpretation, it's certainly valid to view it in a number of different ways in this and many other instances, they certainly have some sort of history, but what it is can certainly be debated.
I mean it'd be nice if it was out-and-out said that they used to have a romantic connection and maybe still have feelings for each other, because this is 2014, and I think we can have openly GLBT characters in all-ages media, if you're okay with hetero relationships being portrayed to kids at exactly the same level of chasteness, then it'd be a double-standard to say otherwise.
Because after all, it is okay to be gay, and suggesting that children exposed to the very notion that homosexuality or transgenderism exists are going to suddenly turn away from heteronormativity doesn't really hold up, if those kids really are swayed by recognition in the media that gay people exist and that they're not evil, it's because they already have those tendencies, and that media is just helping them realize that's a valid way to live as well, which frankly we need a little more of in today's culture, with certain sectors insisting that a heteronormative nuclear family is the only valid option, which risks alienating people and forcing them to repress their true selves, that has an actual proven affect of warping people's development, internalizing a self-loathing and delusory level of denial that they then project outwards to cope.