Yes. The fallacy is known as false equivalence, and in English is often described with the idiom 'comparing apples and oranges'.
In your example, both examples, murder and cutting in line are ethical violations, however, to conflate the two as equally abhorrent morally would be a profound injustice. (Yes, intended.) Why is it possible that this flaw in reasoning happens?
Well, let's take apples and oranges. Both are fruits, it's true! However, there are serious discrepancies in their characteristics that are being ignored. One is grown in northern and wet places, the other in dry places. One can consume the skin of the apple, but not really the rind (zest excluded). They do both grow on trees, but one is a citrus fruit and one is not. So, as a whole, when one engages in argument from analogy when properties are insufficient to claim some form of identity, one is left with a false analogy. Of course, what makes the fallacy believable (and fallacies need to be persuasive by most accounts) is that there is SOME similarity in properties, just not enough to be engaged in an act of synonymy.
As Conifold points out, by using a false equivalence, one then leads into other fallacies such as an appeal to emotion or a strawman or even equivocation where the fallacy is founded on a presumption that there is a shared meaning where there is not. Your Nazi comment reflects Godwin's law which is a truism about how a generalization of the mildly bad ultimately becomes a false equivalence to Hitler and the Third Reich.