 Money News at 10 and 40 past the hour on WTOP. This is a Bloomberg Money Minute. Young adults often have roommates to handle steep housing costs. Now they're applying the same logic to grocery shopping. The Wall Street Journal reports shoppers in their 20s and 30s are battling high prices by joining the warehouse stores such as Costco and Sam's Club and buying in bulk. Gen Z shoppers represent the fastest growing member group.