(MULTIPLE PHOTOS) I was at a Chinese Buddhist temple recently for "Renunciation Day," commemorating the Buddha (then a prince) leaving his palace and his comfortable life to seek answers to address human suffering. The monks too are renunciates who similarly give up the chance to have a family or a career.
As you can see, the temple was elaborately decorated and the monks (in their conical hats) are leaving the temple and passing along the lined up crowd. The laity put donations in the monks' offering bowls who eventually go all the way around the huge lineup (see the last photo).
On this day, the donating act was ritualized, but historically this exchange between monks & laity was vital to Buddhism. The Buddha and some followers became monks, dedicated full time to the Buddhist path. But they needed material support to live. Conversely, others found Buddhism rewarding but shied from such full time commitment. Hence...a kind of exchange developed.
The laity offered food (or today money) to support the monks while the monks, in turn, instruct the laity, perform rituals for them, and also share the "merit" they've accumulated in pursuing the Buddhist path. It's a karmic exchange - the community benefits from the monks' accumulated karmic merit, their example, and their leadership while the monks in turn are supported in their pursuit by the laity.
The idea that religious exemplars pursue only the religious path while setting aside even a family life is fairly common in Indian religions (e.g. Jainism, Hindu saddhus) and also found in Roman Catholicism. Other paths (e.g. Judaism, Islam, Protestant Christianity, North American Native traditions, African indigenous traditions) have no such vision. Leaders there are to marry and have a family. The difference often hinges on how sexual desire is perceived - as a good or something ideally to be transcended.