I think that the way the DJ is treated at some venues can vary a heck of a lot.
At my hotel residency, the staff treat me well, from the waitress's

, the bar staff

, the duty managers

right up to the general managers and owners. I return the "favour" with loyalty, tins (and tins) of chocs for the staff to pick at during the Christmas Disco's and ice creams for the staff from the local Iceland on the occasional boiling hot Sunday midday when I'm packing away from the night before. Them treating me well, has lead to them receiving that treatment from me, in return.
However, I recall a few years ago, my Step-brother asked me to provide the Disco for his wedding at a large hotel outside Ascot....truely amazing main function room it was domed, circular and (get this) had two floors which could both start off in the basement and raise themselves into position at either ground, first or 2nd floor in the room...nice venue, nasty scummy duty manager.
I was having all sorts of problems with the DM, dispite me drawing on several years of customer service experience, and knowing what what running through his mind, from the hotel point of view. Guests wont want to see a Transit van near the fire doors, the bride and groom wont want "grubby"

disco gear stacked neatly in a discreet corner of the function room. No, the hotel wouldn lend me a clean table cloth (or 4) to drape neatly over the neatly stacked gear, nor would the hotel let me hide the tableclothed gear with the hotels 5ft high, portable room dividers....
Funny thing is...all these "no's" turned to "Of course's" when the Grooms father (my step-dad) came up to the duty manager (DM) and I, mid discussion and pointed out that I was not "just" the DJ, but also a guest of the bride and groom, a paying guest of the hotel that night, step-brother to the groom, step-brother-in-law to the bride and HIS (step)Son....

"so cut him some slack, and plenty of it..." ....DM nil, DJ victorious!
It varies from venue to venue, most definately.