cote most vegans I know do not wear leather or wool or ,eat honey. I don't think I know anybody vegan or otherwise, who is a pianist so I can't answer that!
The problem with dairy, is the constant cycle of pregnancy and losing their calves, for cows. Being constantly impregnated so you produce milk, the hormones pumped into you so you produce much , much more milk than you would naturally, then your calf taken away to be killed for veal, is no nice life for a cow. They're killed as soon as they're too old to be of 'use', although their 'natural' life cycle would be for much longer.
I put natural in inverted commas because cows are not a 'natural' animal, they're a human 'invention', there for us to eat and get milk from.
My other issue with milk (LONG before I became vegan) is that I just can't get my head around it being healthy to consume somethign that another species produces to supply its baby with nutrition until It's weaned.
Eggs, similar. Egg-producing chickens are generally treated appalingly. Intensive breeding being just a part of it but male chicks are of no use and are often thrown alive into a grinder. Vegans tend to want to not be part of such things.
Of course there is the debate as to whether a vegan could/would/should consume eggs from a hen with a good, happy ,healthy life. But that's another thread altogether.