My dad one time tried to put lobster shells down my garbage disposal! Boy, did that NOT work! And he was a plumber!!! On the positive side, tho', he made sure I was well supplied with tools when I bought my townhouse...and he knew how to put them to use to repair the damage!! 

I have a friend who works for the public works department in her town, and rails incessantly against garbage disposals. She says most sewage treatment facilities are optimized to treat human waste and not kitchen scraps.
Except for the occasional egg shells (which, this time of year, are best dried, crushed, and added to your bird seed to supplement the calcium for egg-laying wild birds), nothing really goes down our disposals except "mistakes". Stinky trash - chicken bones, fat/gristle - goes in a baggie in the freezer until trash day. Spent oil, liquid fats, go in an empty jar or can under the sink and discarded when full. I wish I could say I was a better composter. Bunny poo (which is GREAT for the garden) and old hay gets composted, but not much else sadly.
2007 Seven ID8 - Bontrager InForm
2003 Klein Palomino - Terry Firefly (?)
2010 Seven Cafe Racer - Bontrager InForm
2008 Cervelo P2C - Adamo Prologue Saddle