First of all the main reason oil prices are high is OPEC, because they actually decide how many oil barrels will be extracted each day. Why do they set prices so high is for some reasons:
Equipment costs more and more as the oil wells become rare, in sea and at deeper levels in the ground.
Oil is a strategic resource with a high international demand, if OPEC countries wish that the rest of the world obey, they must fasten the “belt”.
There is no alternative, OPEC can do as they wish and people will continue buying oil!