Pretty sure Silas is Comicdom, so they only work on stuff that actively gets them money. Once the money stops they drop it and hop on the next popular series, and repeat.
The main thing here is that the Patreon paywall is going to get them and all their alt accounts banned permanently from MD, due to
Site Terms of Service #5.2.22
I don't think they're Comicdom; their translations and redrawing are usually pretty decent whereas Comicdom was clearly churning out stuff as fast as MTL could spit it out.
That being said, you are correct that Silas largely only works on a series when he's being paid. Occasionally he's stuck with a series he's enjoyed (usually to catch up with the raws) but once the commission is complete and people stop donating he moves on to the next series.
There's nothing wrong with being a scanlator for hire per se, though it does make it hard to want to support them on any kind of recurring basis when you never know if a series is going to get dropped suddenly or not.
The paywalling is going to be a problem though; no arguments there.