It's clear from the term "playing cards," the actual purpose of the playing card. They're cards, and they're for playing. Duh. That's obvious. Why am I reading this site by this over-educated dullard, anyway? Well hold on, there, imaginary bucko. Just because a playing card is a playing card doesn't mean it isn't useful in some other way. What other kinds of cards are there? Birthday cards, get-well cards, cue cards, flash cards, and today's subject, recipe cards.
The goal of a recipe card is simple: it is a compact way to keep track of the ingredients and procedures that entail the creation of a meal or beverage. They can be organized however a person sees fit, stored in a location such as a kitchen drawer or cabinet, and referred to whenever necessary to make the same dish the same way every time. So when printing a pack of recipe cards, why not also print suits and ranks on them and make them useful for more than just cooking and drink-mixing?
Deck one, Captain: Bacon recipes.
The advantage of having recipes with playing card markings on them is that they can be played with just as well as they can be referenced. But this also opens them up to things like shuffling, or luck-of-the-draw, or sleight-of-hand for those magical folks who really want to have BBQ bacon burgers and still want to give their significant other the feeling that they really did pick a card on their own.
Of course, printing recipes AND card markings on the same cards can require some compromises. The limited surface area of a poker-sized deck means that the recipes can't be especially long or complicated, unless the font sizes are reduced (bad idea for readability). It's also generally not possible to include photographs of the dishes, so the prospective Vegas-style chef might not quite grasp what a dish truly is with no accompanying visuals.
There's also the fact that, because print space is being compromised to fit the recipes, there is less room for the cards to be distinct from each other. The Ace of Spades and the royals wind up looking just the same as any other card in the deck, and even the Jokers wind up looking quite similar. Except in a few specific cases, anyway.
Lovely SPAM®, wonderful SPAM®...
And then there's the issue of branded recipe decks, where design trumps (haha) usability in both play and reference. Yes, these cards - like the bacon cards above - do play fine upside-down, but you'll be spending a lot of time flipping cards upright if you intend to use the recipes. These helpfully include information about how long they take to prepare, and a place where one can "rate" the recipes (presumably with a permanent marker, which...I don't feel that's something one should do to cards, but that's probably just me).
On the other hand, the focus on branding also includes specified fonts, in a distinctly 1950s glitzy typeface that makes it somewhat difficult to read, especially at the reduced size on most cards. Not that I ever wanted to prepare any of these recipes (I've never been the biggest fan of the famous canned-meat brand), but very few recipes occupy more than half the card. They could have spared some room, in my opinion.
There's many a toast I'd like to say, if only I could think it; so fill your glass to anything and, thank the Lord, I'll drink it.
As a polar opposite, however, I cite these drink recipe cards. A good adult beverage is much simpler than an entire bacon cheeseburger, after all, so the cards ought to have a lot more room to make the ingredients nice and big, show a picture of the drink, make the name noticeable, et cetera. The problem therein is that they had too much room on the cards, and chose to make the photograph gigantic in most cases, even though some photos only barely illustrate the drink, and they enlarged other things to fill space...but never the recipe itself. Maybe it's less important to be able to read once you're a few drinks into the night, but may your booze-related deity of choice help you if you can't remember whether you needed just one ounce or two of vermouth when preparing that next cocktail. (Because you'll probably err on the side of two ounces, and wake up the next morning on the coffee table, wearing someone else's pants. Remember, drink responsibly!)