Question juridique clé
Whether the Zug closing-hour regime violated federal supremacy and the scope of Art. 71 lit. c ArbG
Solution extraite
The cantonal rules were not pre-empted; Art. 71 lit. c ArbG leaves room for cantonal police regulations on opening hours, including for wholesale-type businesses.
Motifs extraits
The Labour Act exhaustively regulates employee protection, but its reservation clause preserves cantonal police rules on opening hours of businesses. The reference to retail trade is illustrative, not exclusive.