Wherever you will walk around the street or any residence area in Japan you will found in every house have at least 2 or 3 bicycle in front of every house. I was wandered first time and gradually I found the reason behind it.
First reason is actually Japanese people love to riding bicycle maybe because the health consciousness or the tradition.
Secondly the transport cost is too high in Japan. The taxi o its damn costly, if you just go for 10 minutes distance maybe the cost would be 1,500 Japanese Yen. I do not know why Taxi is too expensive in Japan and it doesn't make any sense. This is one of the reason people use bicycle to avoid the transport cost in Japan for their day today life.
Thirdly the convenience store and Supermarket is situated maintaining a standard distance from the residence so to save the time and convenient movement people in Japan use Cycle to come and go for their daily shopping.
Fourthly the easy movement Japan got the perfect road construction way to ride the bicycle. People in Japan prefer Cycle for easy movement as in Japan life is to busy so using cycle could be a time saver for them.
Fifthly in Japan there is no public transport for short distance except Taxi. so for the short distance people cycle to move around.
Above mentioned are the reason I found. Thank you