You're charging me $120 for a two-cent part?!

I recently purchased a new home equipped with a SimpliSafe system, which I mistakenly thought was a great selling point.  Upon moving in, I replaced the door hardware and locks for safety. The new locks wouldn’t fit the smart locks, so I called customer service for adapters. Easy fix, right? Wrong. I was disconnected on the first call. Called back only to be told (after a long time on hold), that I would need to replace the entire smart lock system on both doors! Just because they don’t have any 2-cent plastic parts in stock?? Are you kidding me? What kind of customer service is that? Oh. But wait. They can offer me a whopping 30% discount on new hardware. As if that’s supposed to make up for it!? So far, completely unimpressed with SimpliSafe.