@Nemo:
That thread pretty much convinced me not to have collars on my dogs, even though I'm torn about it in the instance that they could escape (happened one time with Nemo when part of my fence blew down in a windstorm)
Even so, my dogs have the collar chewing "genes" too, so they don't last long if left on.
I had been warned about collars being left on in the house unsupervised. Then Pat posted the note from Dr. Jo - that was enough for me to not ever let them wear a collar out of my sight - inside or outdoors. They only have collars on when I walk them, the minute I'm inside or they are free to run in our yard, off they come.
All 3 of mine have the "collar chewing gene" anyway, so I also don't want to take the chance they chew off a collar and swallow part of it creating a blockage. For me it isn't about the cost of replacing a collar - I get bored so they have many collars & leads, it is mainly about their safety.
Again, my personal preference only!