Why can't People just be logical or even consistent?

Here is something that I really find kind of irritating. This link talks about a young lady, Kristi Burton, who is a law student and has decided to push for making fertilized eggs, people, thus giving them certain rights. To be fair she is just pushing for defining when human life begins but the agenda is clear. Let's ignore the obvious problem with the fourteenth amendment to the constitution. You know the one where people born or naturalized in the United States have all the protections of the Constitution? See the obvious problem there? So let's say we give fertilized eggs these rights and protections. Once they are born, following the same logic, these people now have the right to be treated and raised in a safe environment don't they? How are you going to guarantee that? If we continue the same thought process, shouldn't people be assured that they will be able to eat, have shelter and clothing? Of course it goes without saying that capital punishment executions would need to be banned, since human life needs to be protected. And of course wars and armed conflicts need to disappear as well. The thing is that it would be wonderful if one could ensure that we as a society could protect all human life. We should. But this becomes a slippery slope. Until we can ensure the same general protections from womb to grave, for legal purposes human life begins at birth. Or at least if you are going to protect eggs and fetuses to the fullest extent of the law then that protection shouldn't stop once you're squished out into the world.