Honestly, "tract walls" have long been abandoned. We teach that our people are to get out there and relate to people and not let a piece of paper do it. Get into the community. Meet people. Talk to them. Answer their questions.
As has been said before, I don't see one thing in the Bible that says to use tracts and "open air preaching" is not the norm in Scripture but being with people is.
I find your attitude towards tracts to be quite sad.
It is not possibly to get out there and really build relationships with people in this fast paced society, sometimes the best you can do is get a tract in someone's hand.
I have given out many tracts to people behind cash register's, there were many occasions where it was not possible to really get into a conversation about the Gospel.
Gospel tracts are a fantastic way to share Christ.
1. People can't argue or interrupt the message of a Gospel Tract.
2. The power for salvation is in the word of God, and when we give it out God promises his word won't return void, Getting a piece of paper with the word of God on it to others is good for this purpose!
3. Gospel Tracts are a cheap and efficient way to share the gospel in terms of money and time. Think about it, you can share the gospel with 20 people walking down a busy street in a big city in about 5 minutes.
I will say though that I would much rather confront people one on one, but gospel tracts are must and it's a shame people don't take advantage of them.
To say you don't see gospel tracts in the scripture is a sad excuse, You don't see Church Buildings, Microphones, The Internet, or Cell Phones, but all these things are a great tool for sharing the Gospel.