There is apparently some disagreement as to how a rhetorical question should be punctuated.
It seems to me that both Michael Chambers and I agree that rhetorical questions should be punctuated with a question mark. This is what Wikipedia says:
“Depending on the context, a rhetorical question may be punctuated by a question mark (?), full stop (.), or exclamation mark (!), but some sources argue that it is required to use a question mark for any question, rhetorical or not.”
So you may see people writing rhetorical questions without question marks.
"Won't I be glad to see the last of him". is a rhetorical question, but the writer of the sentence
decided to use a period. I would have used a question mark.