Altcoins can be traded with Bitcoin in an attempt to earn more crypto. You are in an exchange market competition against other traders where a small % of skilled traders win long term and most other people lose. This exciting competition helps identify the rare altcoins with long-term value and utility based on unique features which Bitcoin lacks. People who hate all altcoins frequently have a blind rage which is similar to racism against other humans, since they fail to see some things cannot be done with Bitcoin alone.