How can you possibly have this assessment without looking at the code/infra?
There are many things that affect cost beyond the visible features. The project isn't in a vacuum. It's interlocked with their other services infrastructure.
You can judge Google however you want, but they're not stupid or amateurs. These types of announcements immensely damages their image and affect their customers, if they could avoid it easily as you imagine, why would they not?
They've built the service and run it for many years for billions of people. A more realistic guess would be that for whatever reason, the price is higher than what's visible on the surface and they're not willing to pay it.