I believe it has to do with territory markers or something.

Suzuki means bell or tree. http://www.harapan.co.jp/english/japan/kanji_familyname.htm

Suzuki originally comes from a clanname called Hozumi. One of the many Kumano shrines had a long line of shrine administrators who performed Shinto religious rituals as their main function. They were all from the Hozumi clan. One of their chief rituals was to bless newly harvested rice and renew the crops for the next season. New rice was baled up with a piece of wood in the middle. This wood was actually sacred because the rice deity animated the bale of rice through this wooden pole. The wood (or pole or stick) was called "sei naru ki" (literally "sacred pole"). In dialect variations it became "suzuki." The Hozumi ritualist over time came to be called Suzuki by the fact of performing this very important ritual (rice after all was the staple food the entire community relied on). The Suzuki name became more significant than the Hozumi name which applied to a large, far-ranging clan group. Suzuki priests spread throughout Japan and were quite prolific. In the Meiji Era when all citizens were required by law to register a surname, many chose Suzuki (or the local village chief chose it for them) because it was so prestigious, despite not having any genetic link to the Suzukis who started out at Kumano Shrine (in present day Wakayama). Consequently, Suzuki ranks second only to Sato amoung the most popular Japanese family names.

variously written, usually with characters meaning ‘bell tree’, the name is probably taken from Japan’s lovely pampas grass, susuki. An alternate pronunciation is Susuki. This is one of the two most common surnames in Japan, the other being Sato. Legend says that one Suzuki family descended from a priestly line named Hozumi, of Kumano in present-day Mie prefecture. The Hozumi, in turn, are listed in the Shinsen shōjiroku and claim descent from the Mononobe clan.