Mortgages are different because your house isn't going anywhere. The bank can come get it if you stop paying.

See, over here, banks treat it as a good thing that you never had debt on your name. Throw in a stable and reasonably high income and you can get loans basically on a whim. Because why wouldn't you, being as low risk as a person as you can be.

EDIT: Now that I remember. We have very fucked up quirk in the way credit scores are calculated in Germany. Asking for a credit has an impact on it already, because it is assumed that you need money which makes you a risky person because you obviously don't have enough of it. With the very "funny" side effect that shopping around for a mortgage can have a negative impact on the interest rate you can get, up to the point that it can be difficult to get one at all. The trick is to go through a broker that is not sharing his clients, your, name with lenders.