I've read the first 4 comics and I still don't get it. They kill him off at the end of ever comic, but he keeps popping back up. Is it suppose to all culminate to the obit and see how people will remember you if you die at a certain point?  Can someone explain it to me?

It's about life and the subtleties that we find in it everyday.  The death of Bras de Oliva Domingos at the end of each issue is used as a way of impacting the things in life that he won't get to experience.  Issue #4 really stuck with me after reading it, even shedding a few tears. 
 
Fabio Moon and Gabriel Ba are doing an amazing job at this series.  I can't wait for issue #5, as I know that I'm gonna ball like a baby since Bras is 11 years old in that issue.  Nothing sadder than a kid dying and not understanding why...

With this book being about life, death reminds us that life is a precious gift.  Its not a good thing to think about, but it really could end at any moment.  I feel like the creators of this book would like to remind us of that.  The deaths have a more poignant effect because you get a slice of life story starring Bras, but you lose him in the end.  It does feel like a chicken/egg discussion at times as the death means more after you get to know Bras, but the getting to know Bras is more valuable because he dies.   Maybe the creators are trying to remind that we need to enjoy life while it lasts 

Here’s what I’M GONNA SAY. It’s a real testament to how awesome a company Vertigo is, that Daytripper ever got the green light.  Sure, Brazilian twins Fabio Moon and Gabriel Bá are becoming “names” in the comic book industry, and yeah, The Umbrella Academy (Bá) and Casanova (mostly Moon) have a loyal following, but an original 10-part comic book series in which the main character gets killed in EVERY ISSUE?! That’s called a leap of faith, and one that Vertigo has successfully pulled off time and again, since Counting Crows and Ace of Base were running the show. 
More here:  
http://review2akill.com/2010/06/09/daytripper/

" With this book being about life, death reminds us that life is a precious gift.  Its not a good thing to think about, but it really could end at any moment.  I feel like the creators of this book would like to remind us of that.  The deaths have a more poignant effect because you get a slice of life story starring Bras, but you lose him in the end.  It does feel like a chicken/egg discussion at times as the death means more after you get to know Bras, but the getting to know Bras is more valuable because he dies.   Maybe the creators are trying to remind that we need to enjoy life while it lasts  "