I can see this is going to be one of the daily obstacles here. It was much the same way in Romania when I was there a few weeks last May. That is the shortage of change and small bills. If you take the bus a lot it's especially important to hold on to those coins if you can. I thought if I went to a big grocery store, Disco, I could surely get some change there after buying something but they were asking me if I had any coins. Here though I haven't experienced people trying to rip me off, like in Romania, by after giving them a large bill they don't give it back and say they don't have change.