Hey Botrytis....I've been attending them for 41 years.. also listened or worked in over 30 studios (including AIR London, Electric Lady, Water, Streeterville, Record Plant, Atlantic, Clinton, others ...been in Masterdisk a number of times having my projects mastered on the Duntechs back then...and attended many AES pro audio shows...so I do have some perspective...also designed multiple listening and recording rooms..seen the good the bad and the ugly... Sorry but this was ugly to me.
..... by extension of your main point, .... if others throughout the years, as well as others at the show, were able to produce good sound then that counters the issue you bring up. Although I do basically agree with you that it is not easy and sometimes a crapshoot too set up audio in a hotel room, that's part of the job of running an audio company; to be prepared for this and take appropriate measures..
Moreover, your point also does not address the issue of using music which is so very often insipid and unsuitable in content to really make valid assessments (also the audio company's responsibility) ..and that's not just my observation but one that is long-standing.. and again...a VERY limited number of companies were really there...
but that's what subjectivity is all about... enjoy your audio...if you liked what you heard..good for you. I'll be at many more shows but probably not this one again...but be my guest and go ahead if you liked what you heard.
. Listened to some great sounding, very large, very expensive speakers. 
