With 152 million shoppers expected to hit retail stores this weekend for the start of the holiday spending season, restaurants are hoping to cash in on their hunger with Black Friday discounts. This year, a number of national retailers are planning to start the Black Friday frenzy even earlier than in previous years. Target, Best Buy, Kohl’s and Macy’s, for example, plan to open at midnight on Thursday, rather than the wee hours on Friday, as per tradition. Wal-Mart is starting even earlier, kicking off Black Friday at 10 p.m. on Thursday — before the dishes from the holiday feast are likely to be done. The National Restaurant Association estimated that about 32 million people will dine out while shopping on Friday. Still, shoppers remain in a “frugal mood” this year, retail observers say. Consumers are expected to spend an average of $497 per household on gifts this year, according to The Conference Board, up from last year’s estimate of about $390. However, only 7 percent of surveyed consumers said they plan to spend more this year, while another 40 percent said they plan to spend less, according to Conference Board research. In addition, four out of 10 holiday shoppers surveyed said they expect more than half of their purchases to be on sale. “With the overwhelming majority of consumers expecting to spend the same or less than they did last year, it’s not surprising that they expect a large share of their purchases to be on sale or discounted,” said Lynn Franco, director of The Conference Board Consumer Research Center. Following in the spirit of Black Friday discounts, restaurant chains across the country are offering promotions tailored specifically to this weekend’s holiday shoppers: • Pizza Hut: Despite the big feasts planned for Thursday, Pizza Hut is betting consumers will be looking for ways to feed the crowd through the weekend, starting with “Red Roof Wednesday,” referring to Pizza Hut’s red roofs. That’s the pizza chain’s term for the day before Thanksgiving, when hungry college students return home and out-of-town relatives are looking for a dinner that won’t dirty dishes needed on turkey day. This week the pizza chain launched a new Big Dinner Box promotion, an “epic-sized” box with two medium rectangular one-topping pizzas, eight wings and five breadsticks for $19.99. Kurt Kane, Pizza Hut’s chief marketing officer, said in a statement that the chain was breaking ground “by offering our first-ever pizza value box because we know that our customers need a value-conscious option that can feed a crowd during the holidays.” The chain expects to sell 1 million pizzas on Wednesday — almost enough to cover the length of the Mayflower more than 12,000 times, the company said — and receive 275,000 orders for Big Dinner Box meals.