In addition, not all users are going to want to use whatever font you (the web designer) decided on. I have my preferred fonts on my system, and I expect my browser to use them. How arrogant of the web developer to override the user's preference!

I remember when the browsers even allowed the user to configure a background image for content. You could have all your web sites render over a tiled picture of a brick wall if you wanted. Year after year, we give up end-user configurability and simply hand it over to nameless web designers who decide what is good for us.