Why does W8 have so many security prompts?

First things first. I disabled UAC and I turned off SmartScreen as I find them both annoying. Why do some many programs require Admin privileges when my user account has it already? Why does a program like 7-Zip give me a message that I need elevated privileges when I right click on a zip file and select the option to extract it to the folder 7-Zip lists? I have granted all the 7-Zip...