They've dropped before. Around here, some dropped ~15% last summer and have risen just a bit since then. Not sure they will go much lower unless crude remains at current levels, or less, for at least a few more months.
As far as Americans getting $100+ a gallon oil for $25, the $25 figure reflects the true cost (and some profit) to produce and deliver the product to consumers here. I don't presume to know what makes a similar product 4X the price elsewhere. But it may not necessarily be due to differences in the true cost to produce and deliver the product.