Sketch is awesome because it's cheap and can do most things I need, but when I go to work on a logo or something, it sucks compared to Illustrator's shape builder functionality.
Like... I really just want to be able to subtract pieces off each other, or combine them together so a gradient will work with them... in a destructive way...
In lieu of Sketch, or a Sketch plugin offering this, does anyone know of an inexpensive program that offers similar functionality?
I'm not familiar with Sketch, but I can answer the second part of your question.
You could try Inkscape(dot)org - it's free and Open Source - works on Mac/Windows/Linux. It has functionality similar to Illustrator's Pathfinder tools, but nothing equivalent to the Shape Builder Tool in the newest Illustrator CC.
These are some examples of the functions available in Inkscape, under the Path menu.
Sketch does offer this functionality, like subtracting pieces off each other, or combining shapes. You can find more information on https://www.sketchapp.com/learn/documentation/shapes/boolean-operations/ , where those operators are explained.
If you want to do it in a destructive way, do the desired boolean operations and then click Layer > Paths > Flatten.
It's still not as good, but it will do the job most of the time. Otherwise, as Billy recommended, you can use Inkscape.
