- easy disposal of food waste
- no bad smelling garbage or compost container
- waste containers can be smaller
- take up space in the sink cabinet
- can be noisy
- can get jammed by or damage items which go into the disposer by mistake
- another appliance to go wrong and get serviced
- food wastes add a high load to the sewage system (some areas do not allow disposals for this reason)
- may overload septic systems
- can smell (need to have citrus fruit or chemicals run through them to prevent this)
- can clog and need plumbing disassembled to fix
- uses a lot of water, which you or your local utility pays for
Because I compost most of my food waste, I don't feel any need for a disposer. But more generally, I believe they waste electricity, water, soil fertility and sewage disposal capacity for very little return in convenience. In fact if I moved into a house with one already installed, I'd probably take it out!
Agree/disagree? let me know!