No, they're not bad, but I just don't like them. I only have 4 birds, so I don't really need to keep track of anybirdy. JB and Beck just chewed their bands, so I had the vet cut them off because I didn't like them. JB and Beck were both big chain pet store birds too.

The rest were pets from another owner, rescues or bought from a bird breeder.

How do birds balance or step up with only 1 leg I feel so bad for the one legged birds.

Have you seen birds tuck their foot up when they fall asleep? I would imagine it's a similar principle. What I'd like to know though, is how the heck do they move around on a perch with one leg? I would imagine they would become much more dependent on their ability to fly.

I met a crimson rosella with only one leg. You're right, he flew everywhere he wanted to be. He was not tame, but he still got around really great. His cage had flat perches and platforms, no normal "perch" perches.

Quite often the bird doesn't like the band and tries to chew it off. It could be annoying or physically irritating to have this unnatural chunk of metal banging around their ankle all the time.

I've encountered wild birds that had only one leg and were healthy and thriving. It's thought that a lot of the one-legged wild birds are the result of a legband accident, where the bird had been banded previously and it got hung up on something, leading to injury and the loss of the leg. A one-legged wild bird might have trouble with mating, since there's a lot of balance and foot strength involved in that. But otherwise they can do just fine with only one leg.

I've heard of bird banders who will amputate if they catch a bird with a useless, dangling leg that was injured naturally and has no chance to heal properly. They figure that no leg is better than a nonfunctioning leg that basically can't do anything but get in the way.

once I was concerned, I wouldn't be able to tell apart my 2 female rabbits, who are a mother and her daughter. People suggested I tattoo them - this is the way to identify rabbits LOL I didn't, they are actually a little different.
I have two cinnamon sisters who kind of look almost identical but I learned that they are actually a little different - just like identical twins are different to their parents ( it's not quite true about cinnamons - they have different patten on the tip of their wings, but remember I wrote that one grew new feathers in the pattern identical to her sister's. Then she kept growing feathers until she returned to her own unique patters so they are easy to tell apart again)

who on Earth is trying to band wild birds and why???

They do it to keep track of the birds out there, because if they're an endangered species, then scientists try to make sure they're thriving. They band them to count them. If there's a bird that hasn't been banded yet, then it's a new bird. That means the population has gone up.

Though these days, scientists microchip them. It's easier and since microchips are on the insides of their body, they don't get caught on things outside.

I see but it sill sounds crazy to me. First of all, they need to capture the birds... then put them thru some kind of manipulation that is totally unnatural by its nature... Brrr... sounds totally bad to me. I think we need to leave wildlife alone.

Population monitoring is hugely important, for birds and other wildlife.
There's still a lot of old-school banding going on. With microchips you have to recapture the bird to read the chip so it doesn't have any signficant advantage over banding, and it's probably more expensive. There's a lot of radio tagging and electronic tagging going on where they can monitor the bird (or other animal) in real time, which has some serious advantages, but it's expensive and the equipment isn't lightweight enough for them to use it on really small birds like hummingbirds. Banding is super cheap and as far as I know it's still the primary method for monitoring bird populations.

Some links:
http://birdpop.org/
https://en.wikipedia.org/wiki/Animal_migration_tracking