It may have been how Robert Grimstad was looking for a weight watchers coupon and driving that caught people’s attention. He was all over the road.Or the fact it was after midnight and the 38-year-old didn’t have headlights on. Most likely, though, it was the fact he was riding a lawn mower down the highway. When authorities caught up to Grimstad just before 1 a.m. Thursday near Madrid at the intersection of 300th Street and Iowa Highway 17, he told them he was out picking up cans.