I don't know who the "they" in your question is but wallstreetsilver is a subreddit which is focused on silver, in other words, it's a forum just like this website is a forum centered on Q. If you're in the US a local coin shop (LCS) should take cash. I'm in Australia so I can't say for sure though.
https://www.reddit.com/r/Wallstreetsilver/ stack silver
Do they deliver physical silver, no questions asked, 100% anonymous without taking insane fees or trying to rip me off?
I don't know who the "they" in your question is but wallstreetsilver is a subreddit which is focused on silver, in other words, it's a forum just like this website is a forum centered on Q. If you're in the US a local coin shop (LCS) should take cash. I'm in Australia so I can't say for sure though.