Hi picsnapr,
Thank you for using Apple Support Communities. It's my understanding you've been experiencing issues completely deleting an app from your MacBook Pro. I can surely understand why this would be concerning, especially if the app strangely returns. I am happy to help get this resolved with you.
Here is some information on ways to uninstall apps
You can uninstall apps you got from the App Store, from other websites, or from discs. You can’t uninstall apps that are part of OS X, such as Safari and Mail.
Apps downloaded from the App Store: Click the Launchpad icon
in the Dock, hold down an app’s icon until all the icons begin to jiggle, then click an app’s delete button
. If you later want the app, you can reinstall it from the App Store.
If an icon doesn’t have a delete button, it can’t be uninstalled in Launchpad. For more information about Launchpad, see Use Launchpad to view and open apps.
Apps that have an uninstaller: In the Finder sidebar, click Applications. If an app is inside a folder, it might have an Uninstaller. Open the app’s folder. If you see Uninstall App or App Uninstaller, double-click it and follow the onscreen instructions.
Apps that don’t have an uninstaller: In the Finder sidebar, click Applications. Drag the app from the Applications folder to the Trash (located at the end of the Dock), then choose Finder > Empty Trash.
If you change your mind before emptying the Trash, select the app in the Trash, then choose File > Put Back.
WARNING: When you empty the Trash, the app is permanently removed from your Mac. If you have any files that you created with the app, you may not be able to open them.
Delete files and folders
OS X El Capitan: Install, update, and uninstall apps
If you try the steps above and the app still returns try starting in safe mode and deleting it again. You can use the link below for information about safe mode and how to use it:
Try safe mode if your Mac doesn't finish starting up
Have an amazing day!