McDonald's is selling $1 Egg McMuffins on its app on Sunday.The promotion comes as the Egg McMuffin celebrates 50 years on the market and as egg prices soar.Egg prices hit a record high in the US in January, with a dozen large Grade A eggs costing an average of $4.95.As the food industry grapples with the skyrocketing price of eggs in the US, McDonald's is going the other way and selling $1 Egg McMuffins for one day.On Tuesday, McDonald's announced it will be selling Egg McMuffins and Sausage McMuffins with Egg for $1 on Sunday, March 2. The deal is only valid for purchases made through the app in the US.The promotion is being held to celebrate the Egg McMuffin's 50th birthday. The product was introduced in the US in 1975.McDonald's menu prices vary depending on location. In downtown Manhattan, an Egg McMuffin currently costs $5.99.The company's North America impact officer, Michael Gonda, wrote a LinkedIn post on Tuesday about the deal. Referencing egg prices, Gonda said customers "definitely WON'T see McDonald's USA issuing surcharges on eggs."Value strategyDipanjan Chatterjee, a vice president at Forrester, a New York-based market research company, told BI the deal fits right into McDonald's value strategy, which includes $5 meal deals and $1 items.Chatterjee said that with egg prices hitting all-time highs, marketing a "$1 value item" that uses eggs "may seem like an odd choice."But it's more of an opportunity because McDonald's now has a chance to position itself as a company that "prioritizes its customers over profit," Chatterjee said.The move is "likely to pay off handsomely for McDonald's," said Mrio Braz de Matos, the cofounder of the Singapore-based branding consultancy agency Flying Fish Lab."McDonald's doesn't just stand for fast food, it also stands for value," he said. "In good times, it matters, but in harder economic climates, it makes this particular aspect of the brand more attractive to consumers."Alexandra Leung, the founder of Monogic, a food-and-beverage marketing and PR agency in Singapore and Hong Kong, told BI that while the deal will be attractive to cost-conscious consumers, its real value isn't in the sales bump, but in "digital customer acquisition.""I think that the measure of success for this promotion might be better evaluated through metrics like app downloads and digital engagement rather than sustained McMuffin sales post-promotion," she said.Soaring egg pricesMcDonald's $1 deal comes as egg prices in the US have soared, partly due to supply chain issues stemming from an H5N1 bird flu outbreak in the US.The average price of a dozen large Grade A eggs in the country hit an all-time high of $4.95 in January.Given the short supply of eggs, supermarket chains have seensell out minutes after store openings. Whole Foods, Trader Joe's, and Costco have imposed limits on the number of cartons each customer can purchase.Restaurant chain Waffle House announced earlier this month that it would start including a $0.50 surcharge on each egg it sold.Shake Shack's CEO, Rob Lynch, said on Thursday that restaurant chains with big breakfast businesses might dial back on eggs and offer more beef and chicken products instead.Representatives for McDonald's did not respond to a request for comment from BI.