Actually the increase in the coffee/tea in coffee shops are not justified.
The coffee shops guys just take the opportunity to charge(make more) money out of it.
The 35sen increase is for 1 kilo(which can make tens of cup of coffee),but they increase between 10c to 30c EACH CUP!
Even if they don't increase the price after the sugar price increase,they still make a good profit.
So every time there is an increase,those coffee shop burgers make more.