Rhetorical Greetings

This issue has honestly bugged me since about 1996. Don't get me wrong, I haven't been sitting here for 10 years shaking my fists in fury, but WHY do people say 'how are ya.. alright?'. Why bother asking someone how they are if you're going to answer for them? It then becomes a rhetorical question, yet you would be rude not to answer. So what do you say? 'Good.. yes?'