With Japan having a smaller overall pop that comparison is obviously going to favor Japan.

True, but you can just tell at a glance that it wouldn't matter; Japan's population isn't small enough to not make those numbers a drastic per capita difference too. As someone else pointed out, though, it's not because Japan loves the poor, it's because they don't tolerate and incentivize that shit. They don't take care of their homeless, per se...you're just not allowed to be homeless, and you don't get paid for it.

Just for the sake of curiosity: If Japan had the rate of homeless of the US, they'd have around 15,500 homeless in Tokyo alone...more than five times the alleged number of the whole country.