I’d imagine the prices they pay are based on what is selling. The scythe is massively popular everywhere but rokslide so they probably realize that buying bunch of 400-500 dollar scythes and selling them for 7-800 is a good idea.
Unknown munitions seems big on rokslide but I don’t believe it’s nearly as popular elsewhere, they probably have some brand new unknown silencers that havn't been big sellers so they don’t want a. Inch of used gen1 obsolete models tying up space and money.
I’ve only seen the UM stuff talked about here on rokslide and on the rare occasion I see somebody on Facebook talking about them….its a rokslider asking the same question they asked on RS.
At the end of the day, UM is a small company that just started making silencers and they aren’t competitive with the big names in terms of sales volume.