I would like to request you to go through the definition of the term "lay off" u/s 2(kkk) of the Id Act,1947. The reasons cited in the definition are exhaustive and not illustrative. Therefore, the employer can not resort to lay off his workmen for every reason of his temporary inability to provide employment to them. This is my answer to your third question.
Coming to your question no.1, what the news item presented is the impact of the slow down in the over all automobile sales during the particular period on auto component manufacturing units dependent on large automobile manufacturing companies. When their total no of workmen on their rolls EXCEEDS the numbers fixed in sec.25-A(a) or Sec.25-K(1) of the ID Act,1947 they have to pay them compensation as stipulated u/s 25-C of the Act apart from obtaining prior permission to lay off in case of the strength of 100 or more workmen. Since the so called " sales slow down " cannot be a valid reason for lay off, they resort to closing down of production lines for one or two days in a week. It would automatically mean that such days are holidays with wages only. Yet another facet of such a move would be no work for contract labor engaged in such industries.
Regarding your second query, there is no such legal nomenclature as "staff" for white collar employees. When they fall within the ambit of the term " workman" u/s 2(s) of the Act, they could not be laid off in violation of the provisions cited supra.