Horror and spooky themes have been a popular form, for a number of products, especially children's sweets and snacks. Advertisers are very clever in releasing a product that will attract their consumers, they only have to come up with some sort of theme that they know will sell a product. They can put a theme to any item, whether it is connected to the theme or not. Film and TV characters are especially very popular amoung children, monsters are another.
One such product from the 1970's was the corn snack made by Smith's Crisps [now Walker's]Horror bags. These came in 5 different flavored shaped snacks which included Fangs,Bones,Bats,Ribs and Claws. A similiar type snack would come out later-Monster Munch,which is still in production today.
As well as the cool artwork that adornded the packaging such as a top hatted vampire for Fangs and Claws, a skeleton for bones and a bat for bats, Smith's would sometimes have spooky promotional items that you could send away for by collecting so many tokens from the backs of the wrappers. These items included a set of four Horror grippers [see picture above], picture cards, a set of five plastic Creepy Clutchers [see below], a snakes and ladders type game called Serpents and Stairs [see below], a game called Identi-kit in which you had to sort out the sections of card body parts to make up the monsters and lay them in the card graves [something like that]. Take a look at the Identi-kit advertisement from Look-in for the kit below. I remember a friend of mine from school had a black vinyl swimming bag featuring the vampire from horror bags printed on it in white, something he or his parents had sent for from horror bags. I tried for ages to try and persuade him to sell me it, but is parents wouldn't let him. If there is anyone who remembers horror bags and sent for items themselves or have any magazine/comic advertisements please let me know. maybe I could add some more pictures to this post.