Let me just clarify that the lack of citations here is because the question is about attitude rather than facts about animal agricultural practices
At the source of it, for many vegans the idea of using animals is flawed, it implies that they are our property do with what we like.
The situations you mention where they are taken good care of are rare, but let me address each one you mentioned.
Cows only produce milk after giving birth, so they are artificially inseminated (repeatedly) so as to keep producing it. That's not really avoidable even if you're taking care of them.
At this point you're getting lots of calves, females can become dairy cows, males are a burden because you can't send them for slaughter.
Over-production of milk is influenced by the use of things such as Bovine Somatotropin, so the excess you mention is artificially inflated.
Chickens have a fairly even chance to be born male and in the industry those chicks have a bleak and short future ahead of them, however, if you have some chickens in your garden at home, and they lay eggs, they may as well be eaten rather than rot away on the ground.
Plenty of ethical vegans probably won't get too worked up about that, it's a drop in the ocean in terms of egg numbers, but they're not about to go out and get chickens for that purpose either because they won't want to eat chicken periods.
Sheep are bred for maximum wool production, so consequently they need to be sheared.
You have to look at it in the context of the whole system, those sheep exist to make a profit for the farmer, first to produce as much wool as possible, then to be sold as meat.
Honey isn't a by-product, bees collect pollen to make honey to feed themselves. Instead the honey taken has to be replaced with some other food source, that's usually sugar water which is a poor food source for bees.
There are some ways of catching the excess honey that drips out of the bottom of a hive and would otherwise end up on the floor, but that's not going to produce on a scale that makes it more than a fringe endeavour. Again many ethical vegans will not object to people eating that otherwise wasted honey.
So why not eats eggs and honey and wear wool?
First and foremost I don't feel like I'm missing out on this stuff, I don't think about it day to day unless someone asks me a question about it. It's not a problem to be solved, I solved it already for me.
But if you wanted to, the only way to ensure the wellbeing of all the animals involved would be to keep them yourself. At that point you're practically a farmer, that's just not going to make sense for a vegan because if you were going to be a farmer you'd grow kale.