Comment by c-riq
That is true, the location proof is only for the hardware whose IP is used for submitting the vote request. However if remote desktop provider / cloud provider / VPN / Tor IPs are already blocked by the voting platform. Then it would require significant effort to acquire hardware in the target geographic region and equip it with a residential IP. Generally the whole setup only makes sense if IP's (or IP ranges) can only vote once per poll. Then large scale manipulations should become impractical.
You are describing an ideal use case for a botnet of compromised home computers. Should command a much higher premium than sending spam.