These are relevant references from the Books where Sumptuary Law is mentioned.
I make no pronouncements on these matters, but report them as I find them.
Arrive at your own conclusions.
I wish you well,
Several weeks ago in Ar there had been some hints of an attempt on the part of the Ubarate, as a social-control procedure, to facilitate its governance, a venture doubtless emanating from Cos, which had reason to fear an alert, healthy foe, to reduce the vitality and virility of the men of Ar, to further crush and depress them. This was to be done under the initial guise of sumptuary laws, ostensibly to limit the adornment and display of slaves, as though there could be much of that sort of thing in the defeated city.
Magicians of Gor Book 25 Page 211
In my turn the stem of the bota was thrust between my teeth, and I drew in, eagerly, gratefully, my ration of water. I then, a bit later, opened my mouth, widely, and a handful of slave gruel, or moist mush, was thrust in my mouth. One swallows it a tiny bit at a time, that one not choke. It is bland, and largely tasteless, but filling, for what one gets of it, and apparently nutritious. It was a far cry from the provenders I had been taught to prepare in the house, ranging from roasted, seasoned bosk and tarsk and fresh plate breads, with honeys and butters, to frosted pastries and decadent, creamed sauces which, in some cities, were outlawed by sumptuary laws.
Smugglers of Gor Book 32 Page 111
"Surely she has more serious opinions," said another, "as to the ranking of the nine classic poets, the values of the Turian hexameter, should prose be allowed in song drama, the historicity of Hesius, the reform of the calendar, the dark geometries, the story of the czehar, the policies of the Salarian confederation, the nature of the moons, the sumptuary laws of Ti, the history of Ar."
Smugglers of Gor Book 32 Pages 199 - 200
It might be added that in many Gorean cities and towns, professional companions are outlawed, their presence being construed as violating sumptuary laws.
Plunder of Gor Book 34 Page 159