These people are protesting legal and accepted activity. If you do not like the activity, work with your representatives to change the legality of that activity. In this case, work with your represntatives to outlaw drilling off shore in Alaska or drilling in the US period. If you go that route, you had best have an alternative that keeps the country running unless you plan on just shutting everything down to stop the drilling (or buying oil from sources outside the US so the drilling happens somewhere else).
Swatting at symptoms can be applauded by some but the end game of such activity makes me believe it is a stunt to get attention. If the goal is to get off fossel fuels, I would much rather see them spend their time fundraising to put solar panels on lower income housing along with changing local legislation requiring electric utilities to move to distributed PV generation for middle and upper income housing.
I'm sorry to say this, but given the best the activity can hope to achieve makes me think it is done as much for personal satisfaction as it is to achieve a noble goal. I have met many a person who is very passionate about this or that stunt protest. A good deal of the time, it is the passion that drives them and not necessarily the goal.
I'm not poo poo'g the goal. I just do not think this stunt has anything to do with the goal (and even less to do with civil rights disobedience).