You're not getting on my bad side. What does it hurt to have feed on them if they don't take it. Like during a flow, it's there if they want it. Otherwise, it'll be there when they do. I haven't heard where it might hurt anything.
I would think if it would contaminate the sugar water in any way, it would also contaminate the stores already in the hives.
Lee, how about #7? If they continue to forage, what difference does it make where they get it?