Rotten egg and Disgusting attitude from the Manager

i went to Super spar in Boksburg The Square last night bought eggs and margarine. as i was busy preparing the eggs on my 6th egg one egg was cracked and rotten, today i call the store and ask for the manager, i spoke to a guy by the name of Frank, i explained what had happened and he said to me and i quote "what do you expect us to do? you should have brought the eggs back immediately before using them" how was i supposed to know there was a rotten egg there as it was in the middle of the pack. his attitude stinks and I'm a regular at Spar, i will no longer go there i would rather go to Pick n pay they treat people with respect. So it's my fault that the store sells rotten eggs, how disappointing. i haven't checked all the eggs i hope they are not rotten too.