When McDonalds introduced salads to their menu, purchases shot up -- but ~no one actually bought the salads. They just felt better about buying the same old unhealthy food from McDonalds when they knew that healthier options were available that they could potentially buy.
This is the same kind of thing. The crazy overhead of FHE means it's not practical for almost any kind of real world computational work. But having it available at all is undeniably technically impressive, and some of that sense of technical refinement bleeds over into your opinion of Google as a whole.
Incidentally, being a business client of Google's who actually uses this (or, say, quantum computing) for $BUSINESS_FEATURE would garner the same kind of positive attention, independently of whether it's technically a good idea.
Finally, if the overheads come down to the level where they are still significant but not insane, GCP is in a great position.
I'll have you know I started picking salads instead of fries in combo meals the moment they became available.
Not that I'm a frequent customer, either before or after.