Prawns straight from the boat are very very different to what you describe. I used to walk to Scarborough jetty (out of Brisbane) with my grandparents in the 80s, buy a couple of kilo from a boat that'd just come in, walk home, spend 15-30 mins deshelling, then prawn and salad cream (yes, it was a British thing) sandwiches for ever.
Prawns straight from the boat are very very different to what you describe. I used to walk to Scarborough jetty (out of Brisbane) with my grandparents in the 80s, buy a couple of kilo from a boat that'd just come in, walk home, spend 15-30 mins deshelling, then prawn and salad cream (yes, it was a British thing) sandwiches for ever.