I siphoned with just a racking cane and tube for a long time and never really had issues. But it always bothered me that I had to hold my thumb over the end of the tube while lowering it into the bottling bucket. It seemed like my arm touched the inside walls of the bucket or the tubing sometimes. So I started using the auto siphon, and it feels more sanitary to me. I may be solving a non-existent problem, but I feel better about it.