I agree with your point about time limitation acting as a an important influence. My understanding is that time limitation influences human behavior in all sorts of ways, which is probably why a substantial percentage of TV ads have some kind of call for urgency ("Limited Time Offer" "Act Now" "Don't Wait, Call Today")

Also, is there a specific name for this sort of advertising behavior? I was interested in looking up more sources on this but I couldn't find any reasonably high quality ones.