International Roaming & Rejecting Incoming Calls

I was thinking about this after my last comment .... in December I went on a cruise in the Caribbean. When I got off the boat in Mexico I got a text message reminding me my calls, texts, and data were covered. In every other port or said text and data were still free but calls were 20 cents per minute. At one point booking.com was calling to change my reservation. Anyway, I didn't answer my phone, I sent the call to voice mail. I did not listen to the voice mail until I got back to Florida. I did not get charged anything for the phone calls I did not answer. There is NO reason that there should be a charge for unanswered calls, even ones that go to voice mail just because the phone is roaming. Which it was when I was in the Caribbean. Therefore, as long as you do not answer the phone, there should be no charge.