I use Casper restricted software for the app, move the app itself to Utilities via a monthly script Incase an update is helpful and moves it I also have a Casper dock item to delete it there, and then use MCX to disable the apple menu link to it.

I killed it with FIRE... so far :-)

~~~~~~~~~
Is God willing to prevent evil, but not able?
Then he is not omnipotent.
Is he able, but not willing?
Then he is malevolent.
Is he both able, and willing?
Then whence cometh evil?
Is he neither able or willing?
Then why call him God.
~Epicurus
~~~~~~~~
Eric Young
eyoung at thayer.org

You're not alone with needing to do this. A few solutions have been posted
On 9/7/11 11:55 AM, "Charlie Reed" <creed at blurb.com> wrote:
here and on the MacEnterprise list.

For us, I use Casper's Restricted Software feature to kill the "App Store"
process whenever it runs. I also display a notice that software purchases
must be made through our IT department.

Other folks go so far as to remove Mac App Store components so that users
can't even use them.

--

William Smith
Technical Analyst
Merrill Communications LLC
(651) 632-1492

I have a script, but not on me, basically you hide the app and change the binary inside the bundle to root ownership

Easy to do, easy to undo..

I use the restricted App Policy. Works like a charm!
--
Matt Lee, CCA/ACMT/ACPT/ACDT
Senior IT Analyst / Desktop Architecture Team / Apple S.M.E / JAMF Casper Administrator
Fox Networks Group