STEERS HEADOFFICE ***** SELLING A 375 ML AS A 500ML

I am a regular at mcdonalds for there loveley milkshakes,however on principal i would rather support local businesses. So i went to steers broadacers and ordered a large chocolate milkshake,i was given a medium as i asked 5 people in the store what size that they think the cup is.they all said the cup is a medium R36.90 at mcdonalds i get a large whitch has more than double volume and more for R40 problem 1 problem 2 when you start to suck the paper straw halfway through the milkshake you start to spit out pieces of paper has anyone even bothered to test the straw before ordering from the supplier how is it possible that steers charges more than double for a milkshake i sent a complaint and only recieved a call 2 weeks later clearly steers is too busy closing 40 stores than to adress issues quickly so many complaints they cant keep up having explained the above as i did the test by filling a steers cup and decantering into a large mcdonalds cup it took 2 and a bit to fill the mcdonalds cup so as i say steers charges double they are both double thick milkshakes. the lady insisted that they all buy from the same packaging company and the containers are the same size saying that a large steers milkshake is 500ml IT CLEARLY IS NOT ITS 375ML the then blames the franchise and says that broachers is in ICU and the shop will be closed the next day when an inspector from headoffice goes there well no large cups on site and no closing of shop absolutly 0 investigation regarding my complaint before contacting me customer service manager that has 0 product knowledge anyway was given a voucher to shut me up PROBLEM NOT SOLVED So i went to broadacers yesterday to redeem for a large chocolate milkshake Guess what i get a medium cup same as before and on the tillslip it says option 500ml THIS IS ***** BUT NO ONE GETS IT so i came home and made a video of the watertest again 2 and a bit less than half the volume for R3 less IT IS IMPOSSABLE TO CHARGE MORE THAN DOUBLE TO YOUR COMPETETOR BOTH DO DOUBLE THICK MILKSHAKE INFACT MCDONALDS TASTES BETTER i sent the video to her her name started with a n her number *** yes there was frustration in my voice due to the incopetance and lack of product knowledge very unprofecional to slander the franchisee infront of a customer when headoffice is at fault the reply i get is i will interact whit you when you learn how to interact clearly the incompetance had to be hidden by blaming me when she can clearly see that she is prooven to be incompetant and not done her homework before contacting me everone in the chain is incompetant the customer service agent and the manager that trained her 1 bad practice blaming the franchisee infront of a customer 2 not knowing what you sell as large 3condesending the customer when they show you clearly in the video that steers is charging double 4 ***** on the tillslip where 375 ml is sold at 500ml phoned at 8am still waiting for lashen to contact me as he only starts work at 9 well now its 10 absoulutly shocking will never ever in my life put a foot into a steers again