I'm not sure if it relates but I read somewhere that Spirited Away is kind of a response for the recent problem that time of coitus. I forgot wether it said specifically on about child coitus or just in clubs :/ maybe that's how it relates to romance?
Well on the other hand, Haku and Chihiro might just see each other more than just friends. They might fell for each other on that time or when they first met. Maybe its deeper than it looks :/ or its just love between family members or between friends. Love does come in different forms.
I think it may have been one-sided on Haku's part until Chihiro came to really care for him by the end of the film. I see it more of an innocent, first childhood romance than a typical romance in that while romantic relations aren't likely to ever happen between them (especially not at that age), Chihiro really came to love Haku when she grew as a person. So while a kiss was never shared between them, their selfless acts toward one-another are strong that it can't be broken easily no matter how long they're apart. I can't see them ever getting together in the future, but Chihiro may still remember her feelings for a mysterious boy whose face and name she can't recall, and that she became a better person because of him.
I'm probably looking too deep into it, but that's what I got out of it. But Kamaji himself points this out, so while it might have been a throwaway-line, it basically confirms there's love going on between them.
I think its labeled romance because near the end they started talking about how Haku and Chihiro were in love. I don't get how its classified as romance when it was mainly in the ending but maybe MAL saw sparks beginning to fly from the very beginning.
Let’s say I posed this question to you: “Can all human souls be bought with money or not?” Now remember, the keyword here is “all”. The answer is “There are times when you can buy them, and other times, not,” right? The human being… sometimes he’ll uphold his pride and conscience even if he’s offered ten billion yen, and other times he’ll murder someone over one yen. ~Izaya Ohira (Durarara)