What e-mails are you getting daily? We only send a once per month newsletter to the ADS-B feeder network and you can unsubscribe from it if you choose. The only other e-mail you’ll get is a site offline notification but again you can disable that on the My ADS-B page if you choose.
There is also a FlightAware daily e-mail that you can enable on your account but that is not specific to ADS-B.