also if you have a feeder with drilled openings resting directly on wood it will seep. I use only glass jars and I get the lids from Dadant as the holes are drilled small enough and glass shrinks and expands less. I agree that leaving honeycomb out for the bees to rob can draw other bees to your yard to rob your hive. A plastic hair clip ziptied to the top bar can clip the comb to the frame.
No, maybe I should do a few more hive inspections before trying to cram 3 hive visits into one trip.