That is definitely not a core behaviour!
It will most probably be a plugin interfering. I suspect it will be the indexmenu plugin as that has happened before
as described in this other forum post.
Pages only scroll when the ID "scroll__here" is present in the page. And that only happens (in the core, i.e. without plugins) either when you preview a page (to scroll to the preview) or in the sitemap (to scroll to the page you are in). (It's also used in the user and media managers, but that cannot interfere with normal pageviews.)
Some plugins re-use the sitemap, and those will create the effect you describe. Please report a bug to the respective plugin author accordingly.