I've only cast three votes on meta this week, and yet I was just awarded the Vox Populi badge. I see there was a spate of awarding this particular badge, but I haven't noticed a spate of meta voting.
We just deployed a change that affects the voting badges. This is why you see a number of these badges being awarded.
For more information about this change, you can see this answer.
Note that there was a bug with Vox Populi only that awarded too many of them (beyond the expected more for retroactive awards) and a fix has been deployed. The erroneous awards have been cleaned up.