Keep the line associated to a phone that doesn't require a data plan.
Edit: As mentioned 2 posts above, this would work for users that still have that $9.99/mo family line.
My plan still says it is $9.99 per additional line for new lines so its not a grandfathering issue. I think they only way you can't is if you're on a MobileShare plan.
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You can pay cash and not have a credit card on file.
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no problem.
I was referring to the people buying the phones after they were blacklisted. After more than one chargeback, eBay/paypal/any credit card processor would refund them all.