It could probably be worth it to keep an active eye on your data even if it remains roughly the same. To keep an established base line, to keep an eye out for changes in environment in specific areas, to monitor the effects of aging, to sell you shit when your eye gets damaged. Probably other evil shit too, or just the paranoid urge to surveil people for no damn reason.

Selling data on people is a lucrative business. Although it is a business and not UBI.