To reduce noise on stands that have expanded metal platforms I have placed sections of carpet on them before to reduce the noise should you drop something or just the noise of dragging your boot across it. If you fasten the carpet to the stand it can cause other issues, like freezing and leaf/snow accumulation or just becoming a platform for coons to take a crap! I typically would cut the piece of carpet to fit the stand platform and carry it in a pack. Other than that teflon/plastic washers can help with noise as well.....but you have to take the stand apart. I have also heard of folks trying to fill the tube frames with expanding foam....this is mostly to keep moisture and bees out, but they claim it deadens the noise as well. I am not sure of that as I have not done it before myself.
My concern about a coating is the durability. Lots of that stuff isn't UV safe or the critters will chew it off......but if it works for you, then go for it.