This is an official government process that's taking place, the vote counter is made by the government, is hosted on the governments website, and with the EU being what it is, they are no doubt inspecting all traffic that comes through their infrastructure. They may not validate the info in real-time for every country, but they have to be keeping an eye out for multiple submissions from the same IP address. Maybe a few would not be suspicious, but hundreds of submissions on a single IP. Even if they rotated VPNs, that's a tall ask. And for what gain?
lol