Why sell the birthright?

When reading the famous story of the selling of the birthright, the question, "Why would Eisav even think of selling the birthright?" is usually asked. The different Mefarshim answer this question in various ways. Rashi answers that there were many restrictions that went along with being in possession of the birthright. If he were to violate one of the prohibitions, his punishment would most likely be death. For these reasons Eisav did not want it. He did not like to have restrictions, and did not want to die because of them. Radak takes a different approach with his answer. First he says that Eisav thought he was going to die during his father's lifetime anyway, so why would he want the birthright since it had no worth while his father was alive? This point contradicts Rashi's answer. If Eisav didn't want the birthright because he didn't want to die because of the strict restrictions, then he must have not been planning on dying for a while. In Radak's first answer it seems as though Eisav is already aware that he will dying shortly.

Radak's next answer shows that Eisav is only interested in great fortune, not just a small amount. Before Matan Torah, the firstborn was not given a much greater inheritance than the other children. Since Eisav knew he wouldn't be given much more than Yaakov anyway, he did not have a problem with selling his birthright to him. Other commentaries provide different answers, such as Eben Ezra's answer, which is that they were poor anyway so Eisav wouldn't have gained much from the birthright.

I like Rashi's answer and Radak's second answer. I don't believe that Eisav thought he would be dying soon and that was why he didn't want the birthright. From what we already know about Eisav's character, it makes more sense for Eisav to not want the birthright because he did want any restrictions or because he wouldn't gain much more than Yaakov anyway.