Actually, @max_brown, I used to feel the exact same way about it just being wood. Changed my mind after watching them take down the big old oak in my grandma's yard last year. That tree was older than her house, home to so many birds and squirrels. Seeing it just gone, a flat empty spot in the ground... it hit different. Makes you realize it's a whole living thing, not just material. So now I get why people make a thing about it.
My neighbor had a huge silver maple that must have been eighty years old come down in a storm last spring. The whole street felt wrong for months after, just this weird open space where the shade and bird noise used to be. Even the crows seemed pissed off and stopped coming around. The city planted a new little tree there, but it's like putting a goldfish where a whale used to live.