Because ITAR only applies to US companies, non-US companies can do and sell whatever they want. My favorite example is CRPA antenna, where they can block the jamming signal, so it was on ITAR. Other countries like Turkey and China doesn't care so you can even buy one of them in alibaba. They got all the money while the US company can't compete because they're not allowed to, so after several lobbying efforts, that technology got downgraded from ITAR, very toxic export control, to EAR, your normal export control.

Another example is high frame rate thermal camera, US companies are banned from exporting cameras above 9 fps, while chinese companies freely sells 50 fps cameras