Why does SHS uses the bridge as antenna's?

[SmartHomePrimer]

You can apparently use a Sonoff Dongle Max and get Zigbee 3.0 or Thread if that’s what you need. Personally, I’m not planning to add a controller to my SHS. I’ve been using both Z2M and the Home Assistant community app to bring entities into Homey. This works incredibly well and you can then use any controller that HA supports, and both platforms can take advantage of it.

SHS and 3rd Party Thread Boarder Router (like Open TBR)

I have a Dongle Max running Zigbee-only firmware as a Zigbee coordinator in Zigbee2MQTT, I don’t use it as a Thread Border Router at the same time