On the G2, if I went to Settings>Call, there was a call reject setting there. It had a check box to block unavailable numbers, and I could add any number I wanted. I also could use what I called a wildcard to block calls.
For example, I could add 1-800. Then there was an option under that to choose beginning, end, etc.
I could just enter the 1-800 and then choose beginning. So all calls beginning with 1-800 would be blocked. Just add 1-800, 1-877, 1-866, etc and get all the stupid telemarketers who "somehow" got my number to be blocked.
Is the functionality missing on the HTC? I had thought that this was a function of KitKat Android.
Would be nice to have back.