Greeters are critically important members of any white Christian church. Greeters communicate to visitors that their church is welcoming and friendly by mastering the proper technique: smiling, saying "good morning" and using their hand shake to literally pull you through the door. Pulling the hand forward is necessary to prevent both visitors and members from stopping to talk with the greeter. This is strictly forbidden.
You might think that sound doctrine is the primary factor in church selection for white Christians, but you would be wrong. Friendliness is actually more important than every other variable combined, necessitating scores of greeters.
White Christians have discovered that they can double or even triple the friendliness of their church by merely adding a second or third greeter at each entrance. The most successful white churches have been known to maximize their friendliness by having the entire congregation form a greeting line stretching from the parking lot to the narthex.