"Double banking" unsuspecting customers "Honoring fees"

I just want to make unsuspecting customers aware of the so-called "honoring fee" I've noticed since last year this fee, but just thought maybe its the merchant, at 1st we switched to cash only at that particular merchant to completely abandon them due to our own personal reasons. Recently I saw the exact same fee going off at one of African's largest retailers, & I thought let me inquire from the bank, because I know when I do make a purchase there is always sufficient funds in my bank acc & the bank debit my acc for each purchase even if it show pending it goes off from my available balance. Now upon enquiring, the bank give me their "standard legal" response, this happens when the merchant do not bank the transaction in the agreed time, when the bank reverse the "transaction funds" bank to the clients acc & when the merchant eventually bank the transaction they need to honor the transaction even if the client used up the fund..... So I did my due diligence went bank on my acc transactions even 6 months to trace the initial transaction with that specific amount & I found a similar amount went off my acc the 11 July, but I do not see any reversals done by the bank into my acc again, as this is indicated on my transaction history clearly in green font colors, but the "fee" however did go off again. What's more rude & unprofessional, was 2 of their "chat" function consultant just ended the chat when I explained these thing to them without my issue being resolved. Though the transaction is R28 something imagine 1000; 100000 or even 1 million unsuspecting clients having to pay these fee every month, so between the bank & the merchants someone is "double banking" if I could coin this term. A mentor of mine taught me every cent needs to be accounted for...so Standard Bank please account for this!