If the Bus Captain tries to insist that you tap your concession
card when you choose to pay cash, you can refuse. There is no legal
reason for him to refuse your coins as long as you have shown your
card.
Cash payment is a legitimate form of payment for public transport.
Stand up for your rights. The quality of service and manners of our
BCs are going to the pits, with rude drivers and abusive behavior
becoming very common. Sometimes, I wonder if they get an orgasmic
thrill out of going that far beyond their duty scope to perform a
narcissistic witchhunt on a commuter when it has been proven and
witnessed that the commuter was in the right.
If Singaporeans do not stand up to abusive BCs, then they deserve
the crap that is being doled out to them.
I have had a BC who had the nerve to pick an argument with him when
I gave him a tongue-lashing when he stopped his bus frequently
along the road and in the middle of a traffic junction and used
language that was frankly verbal outrage of modesty, on a middle
aged lady, asking to do a body search on her without reasonable
proof other than his wild yelling and swearing.