How "promposals" make proms even more expensive

Parents of teenagers who think going to the prom is as simple as getting a corsage and a nice dress or tux are clearly in for a shock. Their bank accounts are, too.

Proms now cost close to $1,000 on average, but one-third of that expense is tied to "promposals," or elaborate stagings in which teens ask each other out to the prom. And April happens to be peak promposal time, when teens rack their brains to come up with clever or memorable ways to ask for a prom date.

Promposals aren't cheap. Visa (V) found on average they cost $324. Some parents and teens are actually generally spending less on the prom itself, which may be one reason why companies are also angling to get into the promposal business. One event planner in New York City told Bloomberg she charges about $500 to create a promposal concept -- and then at least another $2,500 to put it into action.

"Girls who are most likely going to buy our dress are also Googling promposal stories," Devin VanderMaas, director of marketing for dress company Faviana, told Bloomberg. "That's another way for us to find new people and have them discover our brand."

Promposals don't have to be elaborate affairs. Many involve hand-written signs, puns and props, such as this one exclaiming, "Will you dew me the honor of going to prom with me?" next to a cooler of Mountain Dew. Promposals aren't staged only by teenage boys, as girls also create their own requests. Key to the promposal, aside from cheesy humor, is tapping social media to brag about the effort, which has at least one virtue: it's generally free.

Families in the Northeast are likeliest to get hit hardest by expensive promposals. Visa found that they spend an average of $431 on popping the question.

Western families spend about $342, while Southern and Midwestern families will shell out an average of $305 and $218, respectively.

Alarmingly, the biggest spenders aren't the richest Americans. Families earning below $25,000 spend almost $1,400 on proms, while those with at least $50,000 in annual income spend about $800.

Of course, teens pay only about 27 percent of their prom costs, and parents cover the rest.