To opponents, they're civil-rights violators; to supporters, they're advocates for religious freedom. These florists, bakers and photographers who refuse to work on same-sex unions are also small business owners, and while the legal ramifications of their decisions are being determined in courts across the country, their customers' wallets ultimately will reward or punish their decisions.
"When you open your doors to the public ... it's in your interest to serve everyone, not picking and choosing," said Evan Wolfson, founder and president of Freedom to Marry, a campaign that supports legal gay marriage nationwide.
In some cases, it's also the law. Same-sex couples in several states have filed discrimination claims against businesses that refused to work with them. In August, the New Mexico Supreme Court ruled against a photographer who refused to photograph a lesbian couple's ceremony, citing religious beliefs.
"Whenever we redefine marriage, one of the first casualties is the religious liberties of people of faith," said Chris Plante, spokesman for the National Organization for Marriage, which opposes gay marriage.
Wedding vendors who won't work with gay and lesbian couples and the groups that support them say working on same-sex weddings constitutes an endorsement of same-sex marriage, which impedes their freedom of religion.
New Mexico's Supreme Court rejected this argument, saying, "It is well known to the public that wedding photographers are hired by paying customers and that a photographer may not share the happy couple's views."
Florist Jody Fairchild-Vandekrol, owner of Flowers on Fourth in Grinnell, Iowa, said she doesn't personally know anyone who wouldn't work on a gay or lesbian wedding. But the past president of the Iowa Florists' Association acknowledges that it could depend on the local political climate. "If you're in a more conservative community and if you did take gay and lesbian weddings, the town might look at you differently," she said.
Some businesses have benefited when they speak out against gay marriage. In eastern Washington state, florist Barronelle Stutzman of Arlene's Flowers and Gifts has seen her Richland business grow since being sued by the state's attorney general in April, said her attorney, Justin Bristol. Stutzman referred requests for comment to Bristol.
"It's helped her business," he said, saying Stutzman's revenues have grown by 3 percent or 4 percent since her refusal to make wedding floral arrangements for a longtime gay customer made news. "She's received a tremendous amount of support from the community," Bristol said. The publicity generated by the incident has increased her customer base, he said.
(Read more: What wedding crashers are costing the hotel biz)