I have a limited setback on my house and I swear when I replaced their combo router I stopped having people (late at night eating burgers and listening to loud music while browsing) randomly parked in front of my house (presumably they got signal on the street).
I'll never go back to that configuration again so it's not like I can retest.
[1] https://en.wikipedia.org/wiki/Xfinity#Xfinity_WiFi