So now we've ascertained that they drop in all realms.
Furthermore:
Blackrock has free and 'easier' gear because it is a PvP realm, and because it doesn't have PvE. That is the 'counterpart', the idea that there should be more is, in my view, totally wrong. All the things that existed on Blackrock before, easy transmog being one of them, made sense precisely because of that. It added more ''care-free'' content, something other for players to do when they are not playing battlegrounds, arena, or dueling. On a normal realm, PvE and the whole map of the world (of Warcraft) perform that function.
That said, I would like to further dismantle your counterargument by arguing that even though Relentless and unheroic endgame PvE gear is free on Blackrock, it was harder to get the very best ( the Wrathful and heroic PvE gear) on Blackrock than the others, contrary to your claim. That was because the rating requirements do not differ as far as i know, but players who play on Blackrock are people who totally focus on PvP. This means that the competition is harder, and the actual skill and proficiency needed to get the very best gear is bigger. X-realm arena should nullify that, but instead it brings another unfair disadvantage to Blackrock, the discussion of which is for another thread so i'll just mention it here- Lordaeron and especially Icecrown have a great many Shadowmourne wielders. Shadowmourne is much stronger than the next strongest weapon and it gives a very unfair advantage over all Blackrock players in all arenas, because there is no Shadowmourne on Blackrock. Solution: Add Shadowmourne to Blackrock.
Going back to the topic here:
The argument that you responded to, Obnoxious, was just one among several that were out there in this thread. This argument was the only one that was based on a presuposition that transmog should be made equal on Blackrock to what it is on Lordaeron and Icecrown. All other arguments, however, aimed to show that this idea is mistaken, that they should not be equal. It makes little or no sense that transmog should be so hard on a pure PvP realm, although as i said in my original post, implementation of X-realm means that it was now too easy.
So, as BarbieruMarian said last, increasing the drop chance of the scrolls on Blackrock, or another way of obtaining them (implementing the daily quest- this was a good idea- or the ability to buy it for something that you can farm, like honor) wouldn't hurt anybody. Probably, i feel, my posts are not needed for you to understand that Blackrock players need easier transmog.
PEACE