Make that 8.1
If you removed it from Programs and Features, and it no longer appears in that list, but only within the browser Add-Ons page, then you might try a (what else?) reboot, to make absolutely sure nothing is holding onto the old files.
It really ought to go away at that point.
In windows 8.1 itay be enabled in the IE app as well as IE desktop. Try launching the app and disable ot there as well. Note this is just a guess since I do not have a Windows 8 computer handy right now.