You move from the second camp to the first camp when you have to read massive amounts of code and commit logs.

You are also right. Small projects don't need them because you have to time to to look trough the few changes fast.

Linux development would not go as smooth if it would not have rules (that are quite minimal btw.). If everyone would commit code with different indentation and these changes would constantly end in git, it would be chaos. Same for commit logs. It does not matter at all for those who are contribution only time from time, but if it's your everyday job to read trough them it's important.