Why is leaver buster so harsh on bot games?

I got put in low priority queue for 5 games all because i went to get a plate of fruit during a bot match for 5 minutes -_-. Why does leaver buster have the same punishments as in pvp? It's not like 30-0 yasuo will miss me for 5 minutes or 50-0 vayne. I think that leaver buster should not be as harsh in bot games as in pvp. Now i gotta grind 20 minutes of punishment 5 times >:(.