To determine who would best help them accomplish that goal, they could toss the 30,000,000 votes aside each week, and construct some elaborate system to accurately measure each contestant's popularity amongst the general population. To get the most accurate reading, they would need the largest possible sample. They could spend millions constructing this system to rate the contestants and then do their very best to keep it secret, so that they could ignore the vote, yet avoid going to jail for fraud and losing the most enormous cash cow in the history of television.
Or they could just count the 30,000,000 votes, which would obviously be the best indicator of viewer popularity by far.
But people love conspiracy theories.
The unnamed person behind the scenes might not have gotten a raise, was treated badly by management or had something else go bad.
ALWAYS take with a big grain of salt