Raws are useless for injecting, but some people buy Raws to make nasals or eat them. Raws are a lot cheaper. Sterlity is not important in this case and It is easier to measure dosage, because nasals usually require 5-10x bigger dose than injection and oral route requires like 50-100x bigger dose. It doesn't work with every peptide, but in some cases even companies use Raws to make and sell nasals, like Melanotan II.
Semaglutide is available in the form of tablets for oral route, so it would be possible to eat it Raw, but required dosage is almost 100x bigger than injecting and Raws are "only" 10x cheaper than vials. So eating it would be still 10x more expensive than injecting. And you risk damaging your Raw powder very fast with bad storage.