True -- they are everywhere around here!
Next person feels left out
Raffles, all politics is from the top down. If you start in a little community of 50 people, it is from top down. When you go into politics you go there in order to change things, that in your view need changing. You get yourself a constituency that agrees with you by finding out what these people think is important to them on the local level. Ok, you find a small majority of 27 out of the 50. Now you are going to push for this change, and might succeed, but you are forcing the other 23 people to accept this new ruling, even though they do not agree.
Now, since you are the guy holding the power over them, you make all 50 of them pay for this "improvement". You will tax them and burden all, even the opponents, with this cost. The opposing people are really miffed now. But you are a "good" politician, so you find what this smaller group of people would like to have changed. To appease them, you influence (lobby) higher ups on the ladder of political power in your district to give those people what they would like, thereby cementing yourself as the guy who gets things done, even though the last change you initiated was totally against your own convictions, you just wanted to make sure that all of them "like" you, so that you can go on to get more change started, which in your opinion needs to be done. You have compromised your principles in order to have a chance to achieve you objective. But maybe you are a guy with rubber band principles, then you are happy that you can please so many. And you think that will help a country?
To your next issue, what the government is there for: In my view … let's just say I disagree on what your view is about what a government should do.