After opening several stores without much pushback, Elon Musk’s ambition to replicate the Apple experience in Tesla factory stores is now facing potential roadblocks. Dealer associations in a handful of states, and state regulators in at least one case, say Tesla’s stores violate state franchise laws that prohibit factory ownership of dealerships. Electric-vehicle maker Tesla now operates 17 stores in 10 states and the District of Columbia, most in shopping malls. Another six are scheduled to open this fall.