My parents got an adapter from Amazon that allows them to attach an actual standard CO2 tank, purchased at a local gas company, to the soda machine, which they get refilled every so often. The gas company also refills used SodaStream canisters, so they also get those recharged to use as backups when the standard tank runs low.
She mentions people bringing up the Holocaust, gets some moral outrage going, and says “Do not use other genocides to describe this one.” Then some people start laughing, she looks around angrily, and you can see it dawn on her what she just said, in real time