Coins Without Value! Why?

One time, I was exasperated when I can't almost buy something because my money contains two 10 cents and one 5 cent. Here in the Philippines we usually received these kinds of coins (10 and 5 cents denomination) from Malls. But surprisingly, these coins are not accepted in the common market: For your embarrassment, people will tell you, What is that!

The fact that these coins are made and distributed as legal monetary unit, they have value and they should retain their value throughout the country. The government should impose a Law giving penalty to those who will not accept the said currency; because if they will not, most of these denominations will just be thrown into the trash can – definitely, a waste of money.