Laser cutters rule
So what we have hereis 2 pieces of precise laser-cut acrylic wiv 'oles in. This means we can place the feet in a precise and repeatable location. The bare Slice goes into the gap in the first layer. The second has holes for the little feet.
We have round feet because then you can't put them at an odd and aesthetically displeasing angle.
As mentioned, they do fit perfectly into the screw holes. We decided against that as the message is "Don't open your Slice".