I am not familiar with any specific methods of causing a large explosion that access to a 120V AC socket would allow, which not having access to one would not, with what is currently allowed to passengers through airport security [0]; But considering that producing a cigarette lighter or some nail polish remover in the cabin are grounds to be tackled by an air marshal and prosecuted, an electrical outlet is a hell of a lot of accessible power.
[0] kindly disregard my past five minutes' search history, NSA sniffer