May I forbid a user to install apps from the Store?

I want to forbid an account to install any apps from the Store.

Short of finding out the location of the Store app and changing the permissions so that the said account no longer has permissions necessary to run the Store app.

Is there any more sane way to do this?

You can enforce this using a policy. Open either the Local Security Policy (secpol.msc) or Group Policy Editor (gpedit.msc).

1. Go to Security Settings>Application Control policies>AppLocker
2. Right click on Package App Rules
3. Click Create New Rule and then click Next. Choose the appropriate option (probably Publisher) and click Next again.
4. Go to References>Browser and choose the apps you want to block
5. Click Next and then Create

Users should no longer be allowed to install apps. If you used Group Policy, this policy will apply to the orginizational unit it was created for.

Remember, if you used Group Policy Editor, you can push the policy out now:

     gpupdate /force

For more details, see the full article here.