Vodafone charges $60/month for a mobile data plan with 1GB of traffic. However, if you use data without having a plan (as any modern phone can) they charge $11.25/MB. Therefore 1GB of traffic will cost you approximately $11,000.
That’s the same 1GB of traffic for either $60 or $11,000.
I do not believe that there is any possible justification for such a huge discrepancy in these prices. It’s merely Vodafone acting in a rapacious manner in an attempt to maximise profits extracted from those who don’t fully understand what they’re doing with their shiny new phones.