Apps that are installed into the system folder “Applications” will appear in Launchpad. This include apps from the Mac App Store.
To remove the apps from appearing in Launchpad, you have to remove the app. There is no way to hide an app installed into “Applications” from appearing in Launchpad.
To remove the app, simply remove it from the “Applications” folder. To remove the app from within Launchpad, click and hold on the app icon until you see all icons jiggle. The click on the “x” button on the app icon to delete the app. Mac App Store apps that are deleted can be easily reinstall from Mac App Store under the “Purchases” tab.
If you have too many apps, one way to organize the Launchpad is to make use of folder. For example, create a folder to keep apps that you seldom use. To create a folder in Launchpad, simply drag an app icon into another app icon. A folder will then be created that houses the two apps.