I guess because looking around with the d-pad would be even more awkward than walking is.
I encountered two people who were 'tired', one at the construction site and one at the soba bar. The former actually sounded tired, but the other guy was on caffeine or some shit. His eyes were lit up.
It's really quite stupid/amusing that the Mahjongg guy 'stayed up all night playing mahjongg' EVERY SINGLE NIGHT so you can never play it. And the bike guy, Ono-san, comes up with a ridiculous series of excuses including having to fix a bike ASAP every time I ask him for help.
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as for sonic rush i think it's got great art, pretty good music, fun gameplay except for the blind jumps and 'if you're not running right now, you'll die' bits, and the trick system makes the 'hold forward for ten seconds straight' parts more fun. i also like the fact you can choose from two different levels to play if you're unable to beat one, although i'm rapidly getting better at the game so this isn't an issue.