I think the incident is just a manifestation of a deeper social problem. To these people being ungraceful is not something that they are ashamed about. This has to do with value system. Upbringing has a lot to do with a person's value system.
Singapore is a very competitive society, as a side effect in bringing up and educating a child, values like diligence, shrewdness, ruthlessness which is embodied in the word "kiasu" takes precedent over many of the values that is detrimental to the process of natural selection. In this case, it's courteousness, symphathy, kindness and forgiveness. As a result people think only how to advance their own goal, convenience, right or whatever you want to call it, humanity is all Greek.
This tissue phenomena is just one of the manifestation, other social phenomenons like going after seats in public transport rugby style, not flushing in public toilet, crucifying drivers who move one second late after traffic turned green and etc all stems from the same root IMO.