You're not paying $30 extra to opt-out. They're giving you a $30 discount for you to hand over your data.
It's the same way gas stations get away with "charging extra" for credit. Most credit card vendor agreements do not allow the merchant to pass along the 3% or whatever fee to the customer. So what the gas stations do instead is give you a "cash discount".
This is no longer true re: credit cards. As part of the consumer protection package that passed a few years back, charging fees became permissible by merchants.
You're not paying $30 extra to opt-out. They're giving you a $30 discount for you to hand over your data.
It's the same way gas stations get away with "charging extra" for credit. Most credit card vendor agreements do not allow the merchant to pass along the 3% or whatever fee to the customer. So what the gas stations do instead is give you a "cash discount".