For the same reason that "noce" isn't the past tense of "nice". Only verbs have tenses, past or otherwise. However, I do like to say "hice" for the plural of "house". I know that has nothing to do with the question, I mentioned it simply because of the rhyming. Lol:)
There is a loose group who live on this island who pronounce the singular 'House' as 'Hice', but I think that has something to do with which school they went to and how up themselves they are. :)