Halloween has no relevance to Singapore or its culture at all. In North America, it is a vestige of pagan, pre-Christian lore and belief, and in today's secular society, it is largely for children to dress in spooky costumes, and receive treats from participating households. Some schools, offices, and institutions don decorations, and may even allow staff to dress-up for the day. It has become a huge money-maker for costume, deco companies, and especially for candy manufacturers. Adults who are young-at-heart, or just want to party, use the occasion to pursue entertainment. But nobody believes in the underworld origins of this occasion anymore. For the artistically inclined, the craftsmen, the hobbyist, they get to display their skills, and some do come up with really amazing works. In Singapore, other than private parties, it is a big joke! It never existed, nor was practiced ever in history, and the hungry-ghost festival would be its equivalent here. Like the celebrations for the F1 race, it is a time to throw money, splurge, and engage in hedonistic desires. For those who make money from these parties, it is business, the celebrants are customers, for everyone else, they are idiots.
Cheers!