Everyone tier allows for a discount (with some higher priced plans getting an even bigger discount):
"Customers who choose plans with data allowances of 8 GB or below can add a smartphone for $30, a savings of $10, and customers who choose plans with data allowances of 10 GB and above can add a smartphone for $15, a savings of $25."
This is from Verizon's own press/news release about this at http://www.verizonwireless.com/news/article/2014/04/more-everything-savings-coming.html
Thank you for pointing that out. The Cnet article said nothing about the 10GB and higher discount, in fact, it actually said "plans under 8GB".