From an overall current perspective, the bass signal has the highest voltage swing, and therefore the most current for a given impedance. If any speaker were to need thick cables it’s the subwoofer.
Having said this, if you want something relatively inexpensive that works great for bass the Mogami W3103 from Parts Express is a good value. It’s actually closer to 11 gauge than 12. It’s a metric cable so it sits between the two gauges.
https://www.parts-express.com/Mogami-W3103-1-ft.-Superflexible-High-Definition-2-x-12-AWG-103-1023
I also recommend the 3104, but it’s honestly hard to work with unless you are bi-wiring, and then you can get it for cheap at Markertek