When online banking says, "Due to security reasons, you cannot use right-click in this web-site," I fear dearly for the bank's "security."
If you need to reuse code once, it's a fluke; copy it. If you need to reuse it again, refactor.
A website just told me passwords cannot contain the word "script". Um, why!? What are you doing to make that a problem!? //cc @blowdart