I don't find it that odd, but what I do find odd is that in these days of smartphones the software dialers don't make it trivially easy to block incoming calls. You have to choose an app if you want to block calls and most people are understandably a bit hesitant to replace the default app that came with the phone with some third-party one of unknown provenance. This is a pity, because if users could easily share telemarketing blocklists and so on you could shut down abusive calling industries very very easily.