It's a glitch due to different signatures and patch levels in the installers. Feel free to remove Reader, but well, I wouldn't get wound up over 140 MB.
I agree about Reader. But can I unistall one of the two GB-size installs of Acrobat Pro XI? Or is the glitch that they are one and the same?
I had the same issue as your original post only I didn't have Acrobat Reader showing in my control panel. Since no one here seems to have the answer, I decided to uninstall one of the two Acrobat Pro apps to see what happened.
I chose the 1.97GB version since it's the ONLY app by the publisher "Adobe Systems" All my other Adobe 2014 CC apps are by the publisher "Adobe Systems Incorporated"
When uninstalling the (above) 1.97GB version, the standard Windows uninstall dialog box was used. (nothing related to Adobe) After it was completed, I was unable to open PDF's anymore and Acrobat Pro was removed from the start menu (and all programs) BUT the 1.84GB Acrobat Pro was still showing in the control panel.
An interesting note was when uninstalling the 1.84GB version, the ADOBE uninstall dialog box was used instead of the Windows one that appeared when uninstalling the 1.97GB version.
After both versions were uninstalled, I re-opened the Creative Cloud app and re-installed Acrobat XI Pro again. After completed, both apps appeared again so I guess the long answer is "NO" you cannot delete one of the two Acrobat XI Pro apps.
Would have been nice for Adobe to chime in (prior to now) and let us know instead of making us figure it out on our own.
Just thought I'd share this for anyone else experiencing the same issue.