Increased popularity isn't an ulterior (meaning hidden) motive, it's explicitly the foundation for democracy. The whole premise is that we exploit human selfishness for net good by setting up a system that (in theory) rewards making the largest number of people happy. There's nothing ulterior about that motive, it's the point.

Where things go wrong is when money becomes involved, because then the system rewards making the wealthiest people happy, not the largest number. That's an ulterior motive.

Of course one or more people benefit from every piece of legislation. If a legislator does it to get elected then that's the best case scenario for democracy, right?