They should, but the term has been coopted and it stuck. Similar to how the last name of the guy for which the Coues deer was named rhymes with "house" and yet common pronunciation rhymes with "moose".
From the BCY website:
3. Question: What is creep compared to stretch?
Answer: Creep is non-recoverable elongation, unlike stretch which is basically elasticity or recoverable elongation. Some elasticity is necessary. Creep is a problem. It can cause the bow to go out of tune and the peep to rotate. Creep can affect the draw weight and the draw length.
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