I'm sure someone could be the same way about a "Gay Bar" and them not liking that word?
But "male homosexual bar" sounds like crap, and no one is going to talk like that in real life. "Come Worthington, let us motivate uptown and peruse the male homosexual bars in the Castro".. Just like no one in SF calls The Lexington a 'female homosexual bar' - it's a dyke bar, hell, it's not just a dyke bar, it's perhaps one of THE Dyke Bars, its' the original home of Dykes on Bikes, so they seem OK with that. And if that offends you you don't have to call it that, the hip people call it 'The Lex' and you can go that route. But I don't see anyone get smoking hot about it being referred to with the 'D' word, and this is the capital of PC speech.
Same with the T word. Yes, to a degree it could be thought of as diminutive - the ie sound added to the end of a word has that meaning - like a 'hippie' was a 'baby hipster' (that's exactly how the word came about, and only because the writer of the first newspaper story on them had only the North Beach 'hipsters' (who were called Beatniks also) to compare them to). But...BUT...'diminutive' is not necessarily 'derogatory'. And you seem to be treating it that way. It's considered a more 'casual' and even 'friendly' way to refer to something, and most of the time it's not used in any hateful way, nor does it have any intentionally 'demeaning' quality to it.
And, the ->-bleeped-<- label, at least in a public setting, like calling it a ->-bleeped-<-Bar, serves the purpose that 'Transgender' was supposed to serve in the formal written sense (but somehow doesn't), which is casting the widest net, and creating the largest possible group of people there could possibly be in that mix, without having to go the PC (and guessing/labeling) route of assigning all of them, from the most passable post-op to the first time out CD, into the highly segmented sub-categories, and god, no one is right when it gets to that. So, in fact, some of this might well have been brought about by us all trying to create discrete and highly separate classifications of trans persons, so much so that it confused the casual onlooker who just took up ->-bleeped-<- to mean the entire bunch. Remember we have some mighty fine distinctions between words and conditions here, and to the casual onlooker they might not be all that easy to actually see - so, hey, just skip it entirely and find a common group.
& I can remember the term going back to PRE-INTERNET (yeah, I'm that old) days to refer to bars like The Black Rose, and I remember people at the old ETVC (the Educational ->-bleeped-<- Channel - the forerunner to TGSF, and one of the first TG groups in the country) using the term back in the 80s. ->-bleeped-<-Shack has been using it over a decade and a half, and when they started using the world '->-bleeped-<-' was cutting edge hip. There is a woman in San Jose much beloved as The ->-bleeped-<- Mechanic who's been working with people in our community for two decades now. So it's been around and in the community for a long time now.