Currently Being ModeratedNov 14, 2012 8:35 AM (in response to David M Brewer)
Actually you in fact CAN simply copy the app to other locations. Mac App Store apps are all self contained now. In fact, when updating FCP X, Motion 5 and Compressor 4, many of us copy the older version to another folder, then update. If the update is too buggy, move it to the Trash, and move the older version back into the Applications folder. Works like a charm!
There are three factors to be aware of.
1- There is no limit of "5" for apps. You can download to as many machines as you wish, according to the App Store's EULA.
2- You will not copy over the additional media (Library) with this manual copying method.
3- You will have to "authorized" your freind's Mac for your App Store/iTunes account. This means "de-authorizing" it from his own account. If you can't authorized his Mac to use your App Store/iTunes acount, then moving the app won't work. The Mac MUST be authorized for the user account the app was purchased with. Your Apple ID is embedded into the app itself.