This feels surprising for a minute until comes to mind all the little things that would be broken if browsers didn't behave that way. Custom 404 pages to give

This feels surprising for a minute until comes to mind all the little things that would be broken if browsers didn't behave that way. Custom 404 pages to give the user a friendly explaination and further directions, 500 pages with the exception stack trace in our frameworks to debug the errors etc. A status different from 200 rarely means there's nothing that could be displayed to the user.