Checkers Customer Etiquette

We visited Somerset Mall Checkers Hyper, as we have done many times before. We stood at the door where as the security guard allowed persons to cramp up at the door to move in instead of the usual 1m line, so we thought it was strange, then secondly we had to wait a further 10 minutes for a clean trolley because there was no cleaning sheets available to do this ourselves. Eventually getting into the store to buy our essentials, I turn to the shelf to get something, where one of your packing staff decides to move my trolley - with his bare hands, to the side and bump me in the process and just walk away without even apologizing. Now I had to go back to the entrance to re sanitize my trolley and parts of myself. I then noticed one of the staff is busy with the 50% off stickers on goods that will expire that day. I saw a packet of mini ****ins with today's date and asked if I can get a sticker, as it will classify as 50% off. She explained that there is no need, I just need to tell the person at the till and then they will be able to give me the discount (Well this I have done before a few times and never had any issues before). So I go towards the 10 items or less till (as I had 10 items or less) and stood in a queue where persons in front had trolleys and trolleys full, but still was helped at the express till so I just waited. Eventually being helped at the till I explained the mini ****ins was 50% off, the till staff explained that she does not know of this and will call a manager. She called one manager and then she looked at us and just walked away. We then went to manager again and she said that she will find out and after 5 minutes never came back. I then asked the till staff what will happen and she rolled her eyes at me and did not say a word and just stood there. We found an different manager and she explained to me that because there is no sticker on, she is not able to give it to me at the discount regardless of the date, as this is the rule but will make an exception for this one time as we are holding up the line. I asked if she can explain this to the lady who is busy with the stickers as she have told about 4 persons, excluding me, that you can just go to the till. She then laughed and said that this is a managers rule and the staff does not need to know. I explained how confusing that will be, as it is holding up the line and then if she just gave the sticker then this would not have been a issue. She got very rude and started to raise her voice and as we are just trying to talk, as we have done this before and the 50% off is not a new thing and it's not just at this store. She kept looking up at the ceiling as we talked and sighed and then just said that she is the manager and it is not necessary, we decided to walked away and not deal with rude staff any further. Clearly this store is in need of customer etiquette training. I am requesting a response from checkers on the behavior of the staff.