How does unity manage dynamic substance textures?

I am writing a prototype for a procedural space game, and as part of it I am looking at using Substance to assist with making things look a little more unique via its runtime generation of textures.

Now with the preamble out of the way the main question is focused on how unity handles the texture behind the scenes. I am quite new to unity although do know about game development in general. Now usually you want to re-use the texture in memory as much as possible to stop memory swapping, so with this in mind here is a scenario.

I have an asteroid field which has roughly 1000 asteroids, now assuming I was not using substance and was just using 1 texture for them all I would assume Unity copies this one texture into memory, renders all asteroids re-using the texture in memory.

Now if I were to use Substance to generate the underlying texture but created a random seed for each one (assuming each one contains a diffuse and bump), I would assume this would create 1000 memory copies and do 1 render for each one, I don't know if Unity does anything fancy like batching textures together or anything behind the curtains and this is what I am wanting to know more about if possible.

So to summarize the question in a more Q/A style:

Does unity do anything clever with dynamically created substance textures of the same type with different runtime parameter values, or does it just copy each into memory as needed?