Oh, Marilyn

In today's Parade magazine (which I only read when I'm at my father's) Marilyn vos Savant has one of those "puzzles" readers send in. This one is:

What do these words have in common: candle, day, flash, flood, head, high, moon, search, spot?

And here's the answer:

All become new words with the suffix "light"

Okay, I guess. But you know what, Marilyn? "Light" isn't a suffix.

A suffix, according to MWU, is "an affix occurring at the end of a word, base, or phrase", and an affix is "a sound or sequence of sounds or, in writing, a letter or sequence of letters occurring as a bound form attached to the beginning or end of a word, base, or phrase or inserted within a word or base and serving to produce a derivative word (as un- in untie, -ate in chlorate, -ish in morning-after-ish) or an inflectional form (as -s in cats)".

"Light" is a word. "Candlelight" and the rest are compound words, "consisting of components that are words".

I have to wonder. Is my sample of Marilyn representative? Because she seems to make a lot of mistakes for a genius... especially the sort that could be put right with a trip to the nearest dictionary or (wiki/encyclo)pedia.