the system can't handle them, and if the sewer backs up and they trace it to your house as being the source, you may be held responsible for paying the repairs. That's enough for me not to use them.

Could be that a lot of people misuse them too, who knows. When I Googled it, there are a ton of articles out there saying that companies who make them can basically just say they're flushable, there aren't any guidelines. And people who manage sewer systems say a lot of them shouldn't be flushed.