Sorry... I disagree.
It takes 2 hand to clap..... Unless you are saying that
over 50% of each Block of flats are now being used to house FW.....
then it could hardly explain the amount of litters around.
In some sad way..... S'porean now no longer
take pride of their surrounding. Just look at the MRT
station..... 10yrs ago, you hardly ever see any youngest eating and
drinking in the station or trains..... by since the rule have
been relax..... look at the suitation now.... look at
how youngest don't even care ppl are staring at them as the eat
chips and drink bubble tea...... 
It is S'poreans mentality that is the
problem.....
"Ooh... I pay service & conservancy charges what
Ain't it the responsible of someone to 'clean' after
me" 
"Don't worry lah..... tomorr someone will clean the
areas around here, just throw on the floor lor..."
... TRUE again, and I do agree that attitudes of kids these days
are the doings of today's career-centered parents (not that they
could help it) as well as school's liniency towards disciplining
them, sparing much the rod... but I'd like to give locals the
benefit of the doubt, as I do believe CWO has done its job in
squashing the Litter Bug in many...
... however, now that Foreigners are in our midst in housing
estates, they are reviving the littering habit again as they
probably come from lands wherein littering isn't much frowned
upon...
... and I do agree also, that some locals harbours the mentality
that since they have paid hard earned money for conservancy, they
erroneously & narrow-mindedly presumes that they may litter as
they so please, because they have paid for the premises to be
cleaned up...
... but what drives them to do such things & harbour such
mentalities, one should ask? Was it that too much was sharged for
conservancy? Was it that conservancy along with everything else are
annually increased?
... hmmmm... I wonder what or which might be the cause...that
loses peoples sense of OWNERSHIP and or BELONGING?