Sure, I can use the macos built-in screenshot tool - but sometimes I want them to pop. When a screenshot is not for archiving, but presenting to someone else. No matter if it is publicly on a webpage, or just to convey something over Slack - I'm now using Xnapper than fiddle around myself.
Getting a tweakable, professional screenshot with super nice gradient background in basically a click is so much worth it than trying to refresh my brain how I would do it myself, google for a background and so on.
I also appreciate and like the perpetual license model - made it an instant buy for me. I always hesitate with a subscription model knowing I most likely forget I have the card registered, withdrawals ticking every month.