"Why do so many feel a connection — be it kinship or competition — with utter strangers just because they share a name?
"Social science, it turns out, has an answer. It is because human beings are unconsciously drawn to people and things that remind us of ourselves.
"A psychological theory called the name-letter effect maintains that people like the letters in their own names (particularly their initials) better than other letters of the alphabet." -- Stephanie Rosenbloom, "Names That Match Forge a Bond on the Internet," NYT Online, 4/10/08
I'd include things like soyacino in this, because -cino is just a derivation from the diminuitive suffix -ino. It doesn't specifically have anything to do with coffee, it's just there due to to mental association with cappuccino.
And I will be happy to add words to that list! The only example I remember right now is not exactly what you mean, but it's close enough: schoolbus, minibus etc. derive from omnibus, "for all" in Latin.
I'm also reminded that there are other similar constructions in English, where the portion of the original word chosen for creation of a new word is the "wrong" bit for the intended meaning. Why can I not think of any examples? If I could I would be able to make a list.
I have an unusual first name but a very common last name. I'm always surprised how many googlegangers I have, and slightly disappointed. I grew up thinking I had a terribly unique name. But there's still only one me.
And I'm not aware of anyone else who goes by the name "uselessness" online, which I think is just fun. I mean, how many ordinary words are such a chore to say, and contain no fewer than 5 S's? And describe me so well, at that? :-D
googleganger -- another person of the same name, whose records are intermixed with your own when you "google" yourself. I love this word! One could argue for an umlaut over the a, to make the parallel with doppelganger more complete, but either way, this coinage is genius!