Generally, there is no benefit / possibility of spell checking code – I’ve included a number of code samples in my documents and then been frustrated that the spell checker keeps telling me that VARCHAR2 isn’t a word.
However, there are some places where it’s important to ensure that what you type is what you mean. For example, if you have code that references a business event, then you need to make sure that the event name is correct before you start including it in the code. It would be really bad, for example, if you spellt, say, the name of your company badly. Particularly if it was a BIG company that people may need to trust can type properly.
Oh well, at least (as this image shows from my 11.5.10 system) that it doesn’t happen to any large software providers, eh? 🙂