In-App Purchases are already real-money gaming (and gambling). You can already waste your whole finances on lootbox games chasing a rare reward. The only difference is that you can't officially redeem them for money, it only features all the downsides of gambling. So... it's pretty much the same. The division between gambling for fictional items to gambling for money is so small it might as well not be there.
Gaming has multiple meanings in English such as, hunting, gambling, scamming and playing. Though only in context, the term can apply for any of these activities.
I wish there was a clear point at time where "Don't be evil," turned into "Let's be fucking evil." As it stands, all I can tell for sure is that we're definitely at the second.