Why charge extra fee for caller id

I recently got a new cellphone contract from Vodacom Online. While highly satisfied with the new purchase my satisfaction quickly turned to disappointment when I realized could not see the caller ID on incoming calls even if the number was in my contact list..

I called in to Vodacom customer care to enquire about this and I was utterly shocked to find out that viewing caller ID on contract numbers comes at an additional charge of R9.50. I feel completely cheated as none of this was explained to me when signing the contract.

Small as R9.50 pm may seem, why must I pay to see who from my contact list is calling me. Is it even legal to do this like really now??? It seems like it's only Vodacom that does this like it's sort of ripping people off geez.