Weddings are a big business. And it's not just the ten of thousands of dollars the happy couple and their parents will shell out on the ceremony and reception.

Wedding guests also have lots of financial responsibilities, from the gifts to the travel to the pre-nuptial events to the clothes.

According to a CouponCabin.com survey of 2,234 adults, 16 percent plan on spending more than $100 on their friends' weddings this year, and seven percent will see these expenses exceed $500.

Among respondents 18-34, 23 percent answered that they will fork out at least $100 on weddings and 12 percent at least $500.

Perhaps this is why 37 percent of all 18-34-year-olds have turned down a place in a bridal party because of the costs.

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