Mandarin Oriental New York's general manager, Susanne Hatje, said the idea stemmed from the hotel's niche as a "celebration destination." "Engagements are certainly a milestone deserving of a special weekend away," she said. "We wanted to create an extraordinary package for those couples."
It's a neat fit with proposal trends. According to TheKnot.com, 64 percent of brides were involved in ring shopping, with 27 percent actually buying the ring with their groom. If neither the ring nor the proposal is a surprise, that can put on pressure to make the purchase more of an experience. "A lot of this is about making it very memorable," said Jamie Miles, editor for TheKnot.
More couples are also crafting "destination proposals," she said, with 27 percent taking place in a scenic location away from home.
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Of course, packages could give hotels plenty to celebrate, too, in the form of more business. Making a good impression on the to-be-engaged couple might influence them to think of that hotel brand when it comes time to pick a place for other big moments, said Jason Clampet, a co-founder of travel site Skift.com. "They come back there on their first anniversary and their tenth," he said. "It becomes their special moment place."
A good experience might also influence them to think of that hotel brand when it comes time to pick a wedding venue, arrange room blocks for their guests or decide where to stay while on their honeymoon.
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But couples should be careful not to blow too much of their budget on the proposal, Miles said. The average engagement ring costs $5,598, according to the site's survey of brides—and that's just the beginning of a cascade of wedding expenses that can add up to tens of thousands of dollars. Spending a few thousand more on a hotel proposal package could have the effect of curtailing your guest list or cutting other areas of the budget.
"It's important to envision what else is coming down the line," Miles said. "Buy the ring with the entire wedding in mind."
—By CNBC's Kelli Grant