And if taking 30% wasn't enough of an offense, they are now also stuffing search results of people looking for Affinity products with all kinds of ad crap. I can fully understand why they yanked their products from the Mac App Store and will happily purchase the suite directly from them.

Yes but devs usually leave the old version on the MAS and don't remove it entirely.

The risk here would presumably be people unwittingly purchasing an old version?

Neither way seems ideal though. I've seen some devs create a bundle as a way to do upgrade prices, but that's not perfect either.