only poor sinkies do this type of things.
nothing to do with poor leh. i have heard rich or middle well off does that too.
is the thrill of seeing 1 bottle growing after another..machiam raising 1 kid and then another kids slowly grow up.
dont intentionally change coins and stuff in ,no meaning one..drop in loose change daily
twin tower (mix of 50cent and $1 )
single tower ( pure $1 )
took more than 5 years to fill up