Our pack does the "show and sell" mostly in front of convenience stores and pharmacies. We are not allowed to decide locations on our own or take the actual popcorn door to door, but we can tell everyone we know when we'll be there. We sign up for 2 or 3 time slots, even though it's a hassle, because it is a very good lesson in sticking with a job. To stand there for 2 hours in 100+ degree heat after a long day at school is not fun. But I tell my son if he asks 100 people to buy popcorn and only 5 do, he is still a success.
We bring a lot of stuff with us to set up- folding table, tablecloth, brightly colored poster, scouting magazines(as decorations, for my son to read, and to give away), clearly labeled donation jar, "business cards" with our pack's website and how to order online, a stool(they're not supposed to sit but my son needs a quick break), bottled water, and breath mints.
If we don't meet our sales goal, then we can do the next phase of taking the order form door-to-door. My son actually loves going door to door and meeting people who are not in a hurry, but we try to limit it to a few neighbors that we know or have told in advance that we're coming(and don't have giant dogs that scare my son when they answer the door).
I am very unlikely to buy anything from someone going door to door or in front of a store. I might let my son donate a dollar or two, but that's it. The best customers are former scouts or members of the military. It makes me really uncomfortable to be taking money for overpriced popcorn from someone who has just lost their job.