It is the color. The truck is red, the car is grey.
Swap color and rerun the test and see.
My car is red and I get all the chicks I want. But as I'm happily married, devoted and monogamist, that does not say much about the car
Though there is another factor at play here.
If there were no cars, just a sign saying 'Wasteful' for one and 'Thirfty' for the other, or something along that line, what would you think the outcome would be?
Show a flurry of feathers even if may kill you or forget about sex, that's natures wise lesson.
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2011 Honda Insight + HID, LEDs, tiny PV panel, extra brake pad return springs, neutral wheel alignment, 44/42 PSI (air), PHEV light (inop), tightened wheel nut.
lifetime FE over 0.2 Gmeter or 0.13 Mmile.
For confirmation go to people just like you.
For education go to people unlike yourself.