Historically, maple syrup is the cheap source of sugar in New England, and was used to sweeten things like Boston baked beans. (Very good if done properly, and only slightly sweet.) A relic of this use is the rating code for maple syrup, which is based on how mild the sugar based from the syrup would be; the highest rating, AA, has the least maple flavor. (My husband and I always preferred B for table use.)

Which is to say, if you are a sinner and believe in sweet cornbread, maple syrup would be a perfectly appropriate (if expensive, in modern days) way to do it.