An Aadhar card is just an identity document. You don't have to get one if you don't want any benefits linked to it. Just use some other ID.
Having a mobile number from a non-government entity is not a benefit provided by the government. Yet, the government's Department of Telecom (DoT) issued a notification asking all telcos to verify their subscribers using Aadhaar.
There are many other cases where the government has blatantly violated the Supreme Court orders that Aadhaar shall remain voluntary and that nobody shall be denied a benefit for want of having it.