Don't be discouraged to see Gospel Tracts discarded after you pass them out. God has used countless "recycled" tracts to bring salvation to souls. Following is one such story received from a third-world country about the Gospel periodical, Moments For You.
I gave my life to Jesus Christ through the work of your magazine, Moments For You. I was living in sin and a miserable life, though I am a churchgoer. I attended service every Sunday, yet I didn't know Christ. I didn't know what it meant to be saved, though I was a communicant.
One day a page of Moments For You was used to wrap a fish for me. After I was finished eating the fish, I used it to wipe my hands. Later I opened it and read where I could see clearly the words, "If we say that we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness" (1 John 1:8,9).
After reading it again and again, I fell on my knees and confessed my sins to God and found forgiveness.
Trust God to use the tracts you distribute, and don't ever forget to pray.