My grandparents' home never had a garage disposal, despite one of my uncles offering to buy and install one, my grandmother refused. My parents had a disposal, but over the years and after having a plumber out to clear our main line a number of times, then one day removed the disposal and never looked back. Sewer problems since removal, very, very few. Inconvenience of not having a garbage disposal, none.
Yes I have a disposal in my home, but I never put anything in it which the disposal has to really "work" to "dispose of" (bones, etc). About the only items that do go in it (rarly) are plate scrapings after meals and fruit & vegetable trimmings. I NEVER put coffee grounds, egg shells or any type of fat or grease, solid or liquid. Other then tree root intrusion into the main line, we have not had other sewer problems.