Because honor is nice, but winning is much nicer.
Now, see, that would make sense if the situation were the one I described in the first sentence of that.
This is more like walking nonchalantly past the 5-year-old, then slipping your foot back, tripping him, punching him in the gut, grabbing his candy bar, and running away.
If you had just run up to him, grabbed the candy bar, and run on, you would have achieved the same effect, and not look like such an unmitigated !@#$%^&.