Although Yes, this does have the potential to be "some what" problematic, it really depends on how tight your security is in your Network.
Any person that has elevated priviledges or a "not properly" locked down system can much more to "hurt" your network with malicious intentions.
Also, someone would have to know specifically, what they were looking in terms of "process" for in order to do this.
-> Of course you could remove access to the "Task Manager" and would be a "semi workaround" to not allow this to happen. But than you have the command line, where a TASKKILL /pid:[ID] could be used to terminate the process... This should most likely pop up an "Error 5: access denied" because the users should not have the rights to do this.
Furthermore, as Sandeep indicated above, there are ways around it in the registry, which in my opinion, should be locked down from users and they should not have access to play there.
The same goes for the ADD/REMOVE programs (appwiz.cpl) applet. No end-user should have access to this and should be locked down via GPO.
So if, they don't have access to the Add/remove applet, and cannot edit the registry, there is no way to begin the uninstall process without being "savvy".
I mean, a motivated person could figure out the "product ID" and from a command line, start the MSIEXEC.exe [productID] /uninstall and when prompted for a password, would run the taskkill command and from there "successfully remove the AV" from their system. A log should be generated from this and you should have your reports configured to notify of such events. Auditing of the workstation will tell you who was logged in at the time, and "tampering with a Workstation" that much and with that much motivation to remove the AV/NTP should be a clear indication of malicious intent and grounds for termination.
Honestly, yes it is a "bug" in the system, but should also be an indication to an administrator of the holes/flaws in their internal security