Installation restriction at work. You may have rights to execute .exe but not to install app.
I also have a dozen of utility app I daily use (image viewer, PDF viewer, process killer, inkscape, gimp, etc...). I just have to zip my progs folder to backup and I won't need to reinstall everything if my computer die (which happened last month BTW).
Myself. I'm very curious to see how I look from the outside.