It does seem weird... but if you listen to the director's commentary, they'll tell you that everything (including hanging the GI Joe out the window) is based on things they did in their youth. The whole draw a pic and 'build her a cake' thing is based on a custom that was the norm in their days.
So there is a method to what may seem like madness.
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We are one, we are strong... the more you hold us down, the more we press on - Creed, "What If"
AS is definitive. Reality is frequently inaccurate.
I'm the same as I was when I was six years old - Modest Mouse