Read this, it turns out that syrup made from beet sugar can not be identified by 'isotope' analysis, so it is impossible to tell if honey contains it. Cane sugar syrup can be identified though so it does not get used as much.
https://honeybeesuite.com/is-your-honey-cut-with-sugar-syrup/
Another way to get more honey is to feed your bees on sugar syrup rather than have them flying round looking for flowers. They eat the syrup and turn it into 'Honey'.
Waterboatman, getting your honey from the farm does not mean that the farmer has not fed the bees on syrup to increase the yield. The problem is very widespread and is not illegal, the product can still be called honey. As I just said, if the syrup is made from beet sugar it can not be identified as such. Virtually all beekeepers feed sugar syrup to some extent, in bad weather there are too few flowers so they have to feed sugar syrup to keep the bees from starving.
answers the question
in short they eat the honey they have made- -
( Darwin would confirm: honey bees didnt sit down and think with pencils in their mouths - oh what can we do to help Humans ? Oh I know ( well we know) we will make honey for them to eat ....
altho at the time he was doing his stuff 1859 there WOULD be people around who would say "that is in fact EXACTLY what happened"- god made the world and it is unchanging etc)
Most of Ozs' honey is produced by introduced European bees.
The best honey comes from native bees, which are not good producers.
In Oz different plants flower in different seasons. There is always some thing in flower.
Try some Iron Bark honey one day, very dark and rich.