Are SS are OK asking for my mates contacts

So due to some personal reasons we have social services involved about my unborn child and they were asking me about my social circle around where I live as I moved here last year not knowing anyone. Anyway I have some friends that live across from my house who are of similar age have a 4yr old n we are quite friendly with them so I told social services this today and for some reason they want their contact information which I think is way to far in my opinion as its not like they will be baby sitting or anything like that at most I'd meet them in town for a drink once in a while but why do they need their phone numbers what questions r they gonna ask I feel awful to them as they have a 4 Yr old and when he isn't there they smoke weed so what if I end up screwing things up for them too...i feel like this is way to far into my privacy I understand they need to investigate me but why my friends they have family members who I've given the contacts for but I only have these people who I've known for a few months as they moved opposite me n we have been really friendly but not that close. Why the hell do they need to talk to them.