New Year's Eve
The New Year's Eve celebration dates back to a former pope named Silvester the First (reigned from 314 to 335 AD). Silvester was Pope and Bishop of Rome. He died on December 31, AD 335. Silvester was the first pope who did not suffer the martyrdom. The Catholic Church made December 31st a memorial day for this Pope. Silvester is considered the patron saint of pets and is invoked for a good harvest and a happy new year. Hence the custom of wishing "a happy new year".
The New Year's fireworks have their roots with the Germans. They feared New Year's Eve and put on a loud spectacle. Everyone made as much noise as they could. Wooden wheels were also set on fire and rolled down the valley while still burning to drive away the darkness and evil spirits. From this cult comes the tradition of holding fireworks on New Year's Eve.
Every year a lot of money are spent on firecrackers and rakes. Christians are called to use all material goods or financial means sensibly, that is, in the interests of God and other people, rather than wasting them on futile purposes or fleeting pleasures.
Sources:
Wikipedia
Encyclopedia Britannica
Encyclopedia Americana
Catholic Encyclopedia
Encyclopedia of Religion