In his eight years as owner of Laurel Ace Hardware in East Oakland, Troy Welch has seen how far some thieves will go to shoplift. There was the time someone threatened to shoot Welch’s employees if they tried to stop him from walking out of the store with a stack of garden hoses. The time Welch had to start locking up laundry detergent because so much of it was being stolen. The time robbers ripped off Ace Hardware’s front doors so they could…