Please show me the celebrity/business/politician with even a quarter as many retweets or likes as their follower count.

It doesn't happen. It's an open secret they all buy their followers. They call it 'growth hacking' or 'fake it till you make it'- I call it bullshit.

There are firms that do nothing but increase follower count.

Simply do an internet search for 'where to buy twitter followers'. It's pretty sad its literally that simple.