A popular theory (that I cannot hope to validate) is that imitation is a by product of female birds sexually selecting for better vocal ability in males. Imitation is a way of expressing that. Kinda like a “Look what I can do!” statement.
As much as I hate to use Mythbusters as source material, they did make a fairly doubtless observation about this. A duck’s quack does echo it is just hard for a human set of ears to distinguish between the quack and the echo, both sounding very similiar.
I was not speaking to the claim of “luring by imitating sounds” but rather your assertion that parrots are almost exclusively vegetarian. They aren’t. Granted, most of the animals they eat are arthropods and insects, but that has a lot to do with size. When they can get larger prey they will happily eat it.
Until fairly recently in human history most people got most of their calories from plants, too, but I wouldn’t describe humans as vegetarian by nature, either.
That’s even crazier than the David Attenborough one. Wood saws? Jack hammers? Incredible!
“Pauly”? What the hell parrot calls itself “Pauly”? They’re all “Polly,” even the male ones.
Wild parrots mimic other parrots in their flock. They seldom mimic other sounds, even other bird calls.
Parrots in captivity mimic members of their human flock. They are often given positive reinforcement for doing so (attention, praise).
You forget the positive reinforcement known as “food”.
Once a parrot learns that saying “potato chip” will get a bit of one it will NEVER shut up again. You will hear “potato chip” 10,000,000,000,000 times a day.
This is one reason we do NOT use food to train our birds. Just praise and attention. They’re little monsters when it comes to eating.
A Jersey parrot?
My parakeet can mimic: liquid being poured into a glass, the noise the fridge makes, the microwave’s beep. He can say,"I’m Scout, come ‘ere Scout, Scout bird, pretty bird, dirty bird, hello, how you doin’, I love you and (unfortunately) God Damn it!) All of these he came up with himself. I have never really worked with him. He loves to play with beer caps, any type of lid, spoons, cups…whatever he is capable of moving around. He’s a joy!
What **Broomstick **said. Trigger, the Divemaster’s giant greenwing macaw, happily gobbles down steak and chicken and any other meat (except for bacon and ham. too much salt, which is a no-no) he gives her without hesitation. He makes sure she has a balanced diet that includes seeds, vegetables, fruits, meats and grain.
Dropzone, I’m surprised the bird survived the enhanced Hawaiian Punch encounter. There are others, including mushrooms, but alcohol, avocadoes, caffeine, and chocolate are the four most dangerous substances to give a bird.
Trigger is one smart bird. Scary smart sometimes. She knows me on sight and calls me Peekaboo, even though I don’t see her regularly any more. I got dubbed with that moniker because I’ve played a peekaboo game with her ever since she was a chick. She has a whole repertoire of sounds and names she uses regularly, including calling one of the dogs by name. 
I don’t think crackers are on the parrot menu, since the salt is bad for them.
My neighbor had a parrot that loved to torture the dog and cat by making the sound of the electric can opener and calling “kitty, kitty” Or “here Rex.” Dog and cat came running every time, then looked confused. I wouldn’t be surprised to hear the bird laughing under his breath.
It’s avocados and chocolate that are the worst on that list - parrots do regularly survive encounters with alcohol and caffeine although, yes, those can be fatal. The problem is that it’s very easy for the bird to consume a fatal does of alcohol or caffeine, as their body weights are pretty low and they’re able to consume substantial quantities of stuff for their size. A single swallow of alcohol or coffee isn’t likely to kill a bird, but that much avocado could.
I had a bird that got drunk once - our mouser, in fact. We pulled him away from the alcohol as quick as we could, but not before he got a couple swallows in. He survived with no after effects other than a bad hangover, and never, never, ever drank anything but plain water ever after that, even when alternatives were offered. Which makes him smarter than a lot of people I know.
But yeah, keep the birds and the alcohol separate. Best to avoid such risks.
Too bad this isn’t also the case among humans. There’d be a lot more chicks at Rush concerts…