Same observation.I also observe the same thing when I took
yishun town and feeder bus services such as 804,806 and others,most
of the people just
tap their cards on the exit reader just after boarding the
bus.
SBST has a system that detects how long between your tap on the
entry and exit. If it is much below 45 sec, which is usually the
time taken between 2 short stops, then SBST would check the CCTV
camera for the person [ All ez-link cards have unique serial codes
behind ]. If he DID alight 1 stop, case close. If he didn't, you
know what will happen 
