This is kind of broken logic. You’re not required to advertise. If you want to scale your business into millions in revenue, then you’ll likely need to advertise. The best ROI is generally google/meta, but you have countless other options. You can buy ads directly from most websites, it just doesn’t scale.

The best ROI is google/meta if you're an expert and have unlimited time to dedicate to making and running ad campaigns. For the rest of us there's much better tools that give us better ROI than if we did it on our own.

> You're not required to advertise.

https://en.wikipedia.org/wiki/Arms_race

If you are considering human society as a whole, it is a disastrously poor use of resources. But if you are an arms merchant (or dominant advertising platform), it is fabulously profitable.