[soggypretzels]

What about option 2.5? Rather than hack the hardware, hack the software; buy a cloud-synced scale and sniff the traffic it sends out with the pi.

[Udo]

Wouldn't that be option 1.5? ;)

Yes, in principle. If they are not obfuscating and/or encrypting their data, which is a big if. And you'd be bound to keeping that packet sniffer online forever, piping matching data to where you need it.