Enforcement of the GPL was done way back in 2003 against Linksys and resulted in the OpenWRT project. In Europe the GPL Violations project brought a lot of other cases. So there is plenty of precedent. The principles the FSF and Software Freedom Conservancy use when doing enforcement actions emphasise using legal action as a last resort and not prioritising financial gain (they usually just ask for legal costs and costs for verifying the violation).

https://sfconservancy.org/copyleft-compliance/enforcement-st... https://gpl-violations.org/ https://sfconservancy.org/copyleft-compliance/principles.htm...

They could try to get money but they could also try to get a cease and desist order to compel them to stop if they don’t even post suit. Not sure if that means violating is criminal or anything but means you’re ignoring a court order which is a big no-no legally.