“Bridesmaids” writers Kristen Wiig and Annie Mumolo have always gravitated towards middle aged characters going back to their days at the Groundlings, but a few years ago they decided to start writing a film in earnest about Costco and culotte-loving “mid-lifers.” Both wondered at various points whether they were going to be the only ones who would like what they’d written. That anyone agreed to make it was the biggest shock of all. The end result, “Barb and Star Go to Vista Del Mar,” a neon-hued, cocktail-soaked and music-filled bundle of joyous absurdity, is currently available to rent online.
