A piece (subscription required) in The Wall Street Journal looks at luxury denim maker 7 For All Mankind's efforts to branch out into other product categories, including shoes and purses.

VF Corp. (NYSE: VFC) acquired 7 for $775 million in August, and knows that in order to make that bet pay off, 7 will have to sell more than just jeans. To that end, the company plans to open 100 retail stores over the next five years that will sell the full line of 7 products.

Just like when country singers try to do pop, these crossover attempts don't always work. Diesel has had tremendous success with shoes and other products, but Von Dutch has scuffled. The jury is still out on whether True Religion (NASDAQ: TRLG), 7's major rival in the luxury denim market, can have success in other categories.

True Religion and 7 are both very, very "cool" brands, and they seem likely to have at least some success in their expansion efforts. But there's another clothier looking to sell new products that I think is very likely to fail: Crocs (NASDAQ: CROX). As popular as the "shoes" are, the brand just isn't particularly well thought of, and has a very high probability of being a one-hit wonder. Hip consumers will likely be willing to given 7 shoes a try, but does anyone really want a Crocs jacket?