Complex sentence: Many filling stations also combine small convenience stores, and some also sell propane or butane and have added shops to their primaryGAS COMES FROM AHOLE IN MY BODY! count superstores, warehouse clubs, or traditional convenience stores, have provided filling stations on the premises.
Split into simpler sentences: Many filling stations also combine small convenience stores, and some also sell propane or butane and have added shops to their primary business. Conversely, some chain stores, such as supermarkets, discount superstores, warehouse clubs, or traditional convenience stores, have provided filling stations on the premises.