There is value in every kind of thing we use in this world. The air we use, we have to pay for. The water we use, we have to pay for. If you are to make a house, you don't make it of gold or silver or jewels. That will still be just a house, nothing very special.
Life goes on in the creeping worms but there is great difference of payment of life.
We are not allowed to use anything that creeps on the earth. We are only allowed to have the fruit of the trees and whatever is grown on the table of this earth, that God had been wise enough to guide us and tell us what is most useful so that we can maintain our life with the least burden. God did not really say that it is burden-less or is all free. He has never explained it like this, but He has allowed us to have these lower forms because with our meditations we can release ourselves very quickly and easily and therefore we will not burden ourselves. Some other complications are also there, as now scientists have come to know that all the living beings have some kind of minds and feelings and when they are a little disturbed, their whole nervous system is disturbed and so many poisons are coming up and growing in them.