Seafood sauce is literally just mayo and ketchup, plus whatever amount of tabasco, worcestershire sauce, lemon juice you fancy! It's the condiment version of puttanesca! You're meant to be able to easily make it from cupboard ingredients! It's more wasteful and expensive to buy pre-mixed stuff!
Also the idea of grilled *tinned* grapefruit is genuinely distressing.
EDIT: I also regularly make prawn cocktail for my family (
![Watermelon :watermelon: 🍉](https://cdn.jsdelivr.net/gh/joypixels/emoji-assets@5.0/png/64/1f349.png)
![Shrimp :shrimp: 🦐](https://cdn.jsdelivr.net/gh/joypixels/emoji-assets@5.0/png/64/1f990.png)
) and that recipe is the biggest faff I've ever seen. All you need for a good prawn cocktail are big fat prawns, seafood sauce, and lettuce and maybe avocado for the salad, served with a wedge of lemon. It should take 10 minutes to make, tops, it should be simple.