How come spelled Häagen-Dazs and not Haagen-Dazs?

because the makers wanted the brand name to look more European. the ä was added to make the name seem to be scandinavian. It is not any real language although the ä might denote german, swedish, slovak or finnish, it is not similar to any word in any of those languages. the Dazs seems to be hungarian due to the "zs" but again it not a real word in that language either.

The playful spelling devices in the name invoke the spelling systems used in several European countries. "ä" (an Umlaut) is used in the spelling of German, Finnish, Slovak and Swedish language, doubled vowel letters spell long vowels in Finnish, Dutch, and occasionally German; and zs corresponds to /ʒ/ (as in vision) in Hungarian. None of these spelling conventions is used in pronouncing the name of the American product, which has a short a, hard g, and a final s sound. The closest real name to the fake Häagen is the Danish or Norwegian Haagen or Hågen; Dazs is a possible word in Hungarian due to the "zs" grapheme, but does not resemble any real name.

The brand wasn't European (it was an American company) so they wanted to create some hype to it... The founder, Rueben Mattus was actually Polish but wanted to give the product a Scadinavian feel. On early labels, there was a outline of Denmark.

It's supposed to imbue sophistication like it is an imported product from Denmark or a part of Scandinavia.

Language. Tonal differences and accents make the difference

The spell checker did not have in the dictionary yet.

I like the name Hoggem-Downs better

It's spelt like that because that is how it is pronounced in german.

that is marketing hype . they started in New Jersey , and developed that name to boost sales . seriously .........

cheers !