I'm so glad you brought up the "let's never tell our kid about..." K, who is 3 and half, calls the ice cream truck the "music truck." After seeing our friends' kids have uber-meltdowns when the ice cream truck comes down the street right before dinner, we decided to a) never buy our children ice cream from the truck because if you do it once you will have to do it every time or face the wrath of an ice cream deprived child and b) not even tell our children the truck sells ice cream in the first place. Hence the name "music truck." It's not totally a lie. It's a truck that plays music. How long can we keep it up? Just like your Duplos, I think we have until school. Too bad our children eventually spend time with people outside of our family who will expose all of our half-truths.