From a psychological perspective, 'Free' would be more beneficial since people love free stuff. So more apps are downloaded and people choose to do IAP if they want to (or their kids, if they are not responsible enough).
'Get' may take some getting used to, but it won't be as easy as 'Free'.
Still, I think it serves the purpose. Now people will think twice before downloading the apps.
Personally, I never had a problem with IAP until almost every f'in thing on...