Cicada and Chips?

It has been suggested that, with burgeoning human populations and current concerns about the food chain,  we ought to reconsider insects as sources of human protein even in the UK (http://www.guardian.co.uk/lifeandstyle/2013/mar/02/insects-next-food-source?INTCMP=SRCH). Insects are plentiful, easy and quick to 'grow' (on a wide range of materials) and much less environmentally problematical than cows, sheep, goats et cetera. I know that there is no tradition of eating our caterpillar chums in this country but are they so different from prawns, shrimps and lobsters?