Oh yes, I do it when there's a series I'm reading. My wedding day was the release date for the final Harry Potter book, so on the morning of my wedding I was lining up to get my (pre-ordered) book. I then went home and snuck into the bathroom, and read the final chapter. I had to know! No way I could get married without knowing who lived. I also did similar the other day with the final Wheel of Time book - sat in the car after picking it up, and read the last 2 pages (only - I've invested too many years reading it to find out what happens to everyone, I just needed to know that a certain person lived!)
Also, if I know there are spoilers out there, I will look for them. I won't read them if they are too detailed, I usually just want to get an idea of what happens to one or two characters.
Lol yes I do. I read the first chapter or so then the last five or so pages, then the rest of the book with the last five pages again. Spoilers don't bother me either.
Yes, this is what I do! I find it just helps me enjoy the book more, as I'm able to relax.