We had a pair of beardies a while back, our male loved his vegies, so it's not a male thing. How do you keep your beardies? Do you have a UVB bulb for them that is still good? (Because after about a year on the bulbs, the uvb is no good any more, and like 3 months for the strip UVB bulbs). Substrate? There has to be a reason, and they may just be eating the bugs because they see them move, but not eating the greens because there is something wrong with them.
Oh and I want to add for future reference that to my knowledge you should replace all bulbs after 6 months. Not 1 year. I mean, to keep their effectiveness.