Why, in Pakistan, do we have to save all of our previous utility?
As proof of payment in case future bill has discrepancy or shows non paid. Occasionally there are defects in banking or payment procedures which happen from time to time. Also for tax returns, if you are a filer. You can reclaim paid adv taxes in your yearly refund by attaching bills. Most of the majority just has no idea they are paying extra refundable amount.