I see where you are coming from with this question. When a strong base like sodium hydroxide reacts with a strong acid like hydrochloric acid, the end result is an ionic salt like sodium chloride in water. However, the oceans are not salty because a massive acid/base reaction took place hundreds of millions of years ago. The ocean is salty because over millions of years groundwater has been dissolving natural ionic minerals from the Earth's crust and collecting all of these dissolved minerals in the ocean. These dissolved ions give the ocean water its salty taste. The reason that most lakes are not salty is because water flows out of them over time and ultimately makes its way to the oceans.