It does. It's got better since the war, but there's still the Statute of Secrecy in place so really, the cultural influence only really goes one way. Muggleborns and those who have Muggle relatives bring it in to ours, and the undesireable elements are bound to be brought in as well as the good.
But to be honest, the more conservative people are always going to be complaining about things changing, no matter how innocuous the change.