I honestly find them to be sort of picky at times, myself. Not spoiled, just very picky in what my crew will eat and what they won't. They don't like a lot of the cookies/biscuits that people give to them, and they'll politely take it and say 'Thank you for trying!' then spit it out.
In which case the Corgi promptly grabs it and swallows it. No harm, no foul.
But, I've learned from my crew that the girls are always hardest to keep weight on. I resorted to feeding Ali an ice-cream scoop of lard on her food when we were showing her on a regular basis. XD Don't try that at home unless you have a dog with an iron stomach, though.
However, if they have gotten you to hand feed them? Oh man, that's a bit rough - and kind of spoiled, yeah. My breeder did that when I had to leave Ali with her when we went on a trip; Ali turned up her nose at everything and was being a brat, so the breeder resorted to feeding her a little handful of kibble at a time. When I brought her home, she sat in front of her bowl and stared at me.
I stared right back. "Eat it or wear it."
When she didn't eat after ten minutes, I picked up the bowl, and that was it. No treats, no nothing, diddly-squat. The next morning I put down the bowl, and she went, "BLEAH!"
I timed off ten minutes and picked up the bowl.
Funny thing - she made it through the evening, then in the morning she sat and crunched kibble.
We've played this game a few times over the years, her and I, and for the most part, I win.
When you keep switching out one food for another in desperation? That's when they realize they've got you good. Gabe's great - he's smart enough to work, but not bright enough to ever try that tactic. *grin*
As long as they have plenty of water, don't worry. I don't try that trick on cats, because my cats play Survivor - they can outlast, outthink, and outstarve themselves fast. But the dogs, given a chance, will not be that grudgingly stubborn; they give up and eat. Sometimes adding a little unsalted chicken broth to their dinner or a tablespoon of butter or grated cheese helps, but...
And really, a lot of Shepherds stay thin until they're about three or four. Then they bulk up and fill out. Girls are especially known for this. Fine by me, less weight, less stress on joints.