How are non-pyogenic streptococci spread?

Many are normal.. Inhabitants of the oral cavity, GI tract and vaginal vault and they do not need to spread from person to person. Some strep are zoonoses that can be transmitted from hogs (s. Suis) or fish (s. Iniae).
Normal flora. These organisms are part of the normal bacteria which populate our integument (skin and soft tissues). You cannot eliminate them, but they seldom produce clinical disease without some predisposing factors.
Contact. All streptococci are part of skin flora and can be spread person to person by skin contact.