Doctor Toon, the answer to the first question is easy. People buy things at the last minute because that’s when they realize that they must have them. Wouldn’t that be true by definition? :))
Wait a minute. Strike that. Let me invoke a little Jungian psych here. My personality type is ENFP (as the famous MBTI or Myers-Briggs test would summarize its order of cognitive processes), and I and my fellow Ps by nature tend to wait until the last minute to do whatever’s really needful. In shopping I try to avoid that, and pull rather on the “flip side” of being a P (striking while the iron is hot, spontaneously).
I’ll bet you’re one of the J’s (e.g., INTJ): someone who prefers to plan well ahead of time. Well, each approach has its strengths and its weaknesses (the weakness of the J approach being a potential lack of flexibility).
Why do people drive into closed left lanes? I have no idea.