Hundreds of Tesla owners gathered at the automaker’s showrooms and distribution centers in China over the weekend, demanding rebates and credit after sudden price cuts they said meant they had overpaid for electric cars they bought earlier. On Saturday, about 200 recent buyers of the Tesla Model Y and Model 3 gathered at a Tesla delivery center in Shanghai to protest against the US carmaker’s decision to slash prices for the second time in three months on Friday. Many said they had believed that prices Tesla charged for its cars late last year would not be cut as abruptly or...