Your data has monetary value to google. Giving them access, without getting any money from them (or even knowing what ways it will be used) is not something you must do.
To be fair, while you may not be getting money in its direct form (cash, bank deposit, etc) from Google, they are providing you a service which costs them money for free. So they are providing something of monetary value.
Only the individual can determine if their data is worth that free (to the individual, not free to Google) service. I’m assuming that most people in a privacy community would be against that, though.
That’s what it looks like to the untrained eye. But they’re not really going to fire a person out of a cannon. That’s not safe. So he just huddles in the cannon, they light a decoy fuse, it makes a bang (with no projectile), and he spring out and jumps that distance by himself. Requires a lot of core and leg strength.