That is not JUCE specific, but all bitmap graphics will have artefacts when they are rescaled. They happen less noticeable for power of two scale factors.
You can draw without scaling, but then you are bound to a certain size of your editor. You cannot have resizable UI, which is something to aim for nowadays.
For me the killer feature for vector is, you can scale it on any dpi, vs. with bitmaps, when machines use higher resolutions in the future, you might have to re-do the bitmaps.
In fairness, vector graphics also result in an antialias effect, which is also a slight blur, but since the mathematical model is known, it can still be rendered much more precise than the pixel scaling.
I haven’t used the Saussage Fattener myself. But most of the time, if it is comic art it is often vector graphics, if it is photo realistic, it is often bitmaps.
I have seen crafty people doing photorealistic vector graphics, that are amazing.
One link I found here:
There were more amazing screenshots I can’t find right now…