Our great Dane does this. If he doesn't want a treat, he'll go and put it by our small dogs' kennels for them to have. He also won't eat treats he likes unless the small dogs get one too.
And, oddly enough, he's the only dog I've ever encountered that can free feed (great Danes are notoriously food motivated). But water, though. We have to chase him away from the bowl or he'll sit there and drink the whole thing.
Yup, properly cooked veggies are awesome.
But, children's taste buds are different from adults. Iirc they taste things more strongly, so the bitter notes are more pronounced.
Also, they've been breeding stuff like brussel sprouts to be less bitter for a while now, so veggies might actually taste better than when we were kids.