I back up everything in /var except /var/cache. I also back up /srv,
though it's usually empty. So I really don't mind if important data is
kept in /var, I've always thought that's what it's for.
If someone wants to start moving things around, then that's perhaps ok,
though I would consider it confusing and unnecessary. And the new
location can't be /srv because it has no structure. So you need to come
up with a new directory instead. Then everyone needs to add that
directory to their backup set. See... This is pointless. Let's keep
important stuff in /var/lib/<packagename>, it works.
/abo