"Steal" has been used as "copy" long enough that it's part of the standard usage now (and has been for a long time), just like "literally" being used as an intensifier, or "cool" meaning "good" as opposed to referring strictly to temperature.
And it's likely not even a misconception (like "a napron" => "an apron" was) but rather a conceptual metaphor (https://en.wikipedia.org/wiki/Conceptual_metaphor), which is what helps you understand that you shouldn't be afraid of cutting yourself on someone's "sharp wit", and that you don't need to bring a ladder shopping even though "prices are rising".
Hell, even "conception" (as in "misconception") was originally only used for talking about literal pregnancies, the metaphorical extension didn't come about until the 14th century (source: https://www.etymonline.com/word/conception). Or is that okay? If so, how old does a semantic extensions have to be to be accepted into the lexicon?