Hello Nick from another Nick. In a sense, your question is more one of psychology than philosophy. We philosophers do not so much ask and answer questions about why people actually do things or act the way they do, so much as to inquire about how, perhaps, we should do things, or how we might do them better than we do them now.
Valuing material goods even more than life itself, I think most (if not all) philosophers would agree, is a very serious and ultimately self-defeating ethical error. It is, very simply, to assign greater value to what is in fact far less valuable. But there may be another error here, as well--if we think that life has intrinsic value (as many but not all philosophers do), then valuing wealth over life itself is to mistake something that has only instrumental value--value, that is, only for the pursuit or acquisition of something else that is valuable--for something that is intrinsically valuable (valuable, that is, just in and of itself and not only for trying to obtain something else.
It is generally agreed that wealth is only instrumentally valuable. Just think: If someone were to give you a million dollars, but only under the stipulation that you (and your heirs, and their heirs, etc.) could never spend it on anything, what real value would the money have (for you or for anyone else)? The value of money just is whatever it enables you to do or to purchase--it just is the instrumental value it provides for getting other things. You might think, however, that just being alive is valuable (consider the alternative!).
Of course, there may be other intrinsic values that could come into conflict with the value of life itself. We value not being in pain or suffering, for example, such that too much unrelieved suffering might lead us to conclude that life itself is no longer valuable enough to continue. But such cases do not show that life is not intrinsically valuable, only that there can be considerations that can trump its value.
Some philosophers, however, have said that life is not intrinsically valuable, but can only become valuable if it is lived in certain ways. So Socrates famously said that "the unexamined life is not worth living for a human being" (Plato, Apology 38a), which seems to suggest that he did not think that life itself was intrinsically valuable, but gained value only by being or becoming an "examined" life (one in which critical inquiry was a significant feature is what he meant, I think).
Anyway, it is generally foolish and self-defeating to live one's life as if something that is simply an instrumental value were actually intrinsically valuable, or brought value to a life just by its acquisition. Imagine thinking that one's life would be clearly enriched by acquiring every tool known to humankind, by one who had no clue as to how to use those tools! If one could figure out what was really valuable (intrinsically valuable, that is), maybe then one could figure out how to use money in such a way as to put the money to good use!