I should think that you're right! Some rhymes do seem to have been lost.

To rhyme with Wales, one version above has;
And that was the reason he set off on the rails.

Another version collected by Bob Copper already has;
So we will unite together like birds of a feather.
And to rhyme with away;
Like bees in one hive so contented we'll stay.

So it seems likely that other lines once had an internal rhyme. Depending upon your preference for money or victuals, it might have been;
Much sweeter it tasted than the gold/food he had wasted.
Gold seems a greater loss.