Shoppers are going to the store more often, but buying a little less each trip, according to reports in theWall Street JournalandNielsen.The Nielsen report classified shopping trips, according to average amount of purchase, into these categories: immediate (average total purchase of $15 per trip), fill-in (average purchase of $51), routine ($98) and stock-up ($242). Across all retail channels and shopper income levels, immediate trips fell slightly, while fill-in trips edged upward by 0.7%. Immediate trips dropped in grocery and convenience stores (the latter possibly due to rising gas prices) but rose in supercenters. Packagers who depend on retail channels where smaller trips are increasing are, in some cases, decreasing package size to make their products’ price points more attractive to small-trip shoppers.