Labs are literally dustbins
Everyone always says that... but ours isn't.
She will eat most things that are offered to her, but won't touch food unless she is clearly given a signal that it's for her.
For main meals, our three get raw food mixed in with various dog-safe fruits and veg, and some 'raw' biscuits, which are like kibble but made from vegetables and proteins and other similar safe stuff.
Everything is low in fat, as one of ours is susceptible to pancreatitis.
They also get occasional snacks of raw meat (chicken wings, and the like) and raw veg - Carrots are good for the teeth.
Being rescue dogs, when we first got them they had been fed on all the usual crap, like Winalot and Pedigree Chum and dry kibble stuff. They used to eat each others poo, but that stopped once we switched to raw food... the theory is that what came out smelt the same as when it went in, which was an indicator of the low quality.
The Lab can really hoover up food, but even she will turn her nose up at the cheap crap dog foods now - If even yer dog won't eat it, you know it's crap!!