Google cites these applications violate certain terms that developers agree to, by interfering with or accessing another service in an unauthorized manner. It might suck for people who love ad-blockers, but Google can’t have you messing with their revenue stream.
Here is the email Google is sending out to offenders:
This is a notification that your application, Ad Blocker ★ Root ★, with package ID com.jrummy.apps.ad.blocker, has been removed from the Google Play Store.
REASON FOR REMOVAL: Violation of section 4.4 of the Developer Distribution Agreement.
After a regular review we have determined that your app interferes with or accesses another service or product in an unauthorized manner. This violates the provision of your agreement with Google referred to above.
All violations are tracked. Serious or repeated violations of any nature will result in the termination of your developer account, and investigation and possible termination of related Google accounts. If your account is terminated, payments will cease and Google may recover the proceeds of any past sales and/or the cost of any associated fees (such as chargebacks and transaction fees) from you.
If your developer account is still in good standing, you may revise and upload a new instance of the application that is compliant with the developer terms. Before uploading any new applications, please review the Developer Distribution Agreement and Content Policy.
If you feel we have made this determination in error, you can visit this Google Play Help Center article for additional information regarding this removal.
The Google Play Team