The calling cards or business cards are always useful to me, I often get one on some shops or other business establishment I had been visited. I collect those contact information or brochures that are given away in case one day I need to make transactions or have some inquiries.
Like last time, I went to the seafood shop nearest to my place to assume and just feeling lucky if they have the product I'm looking for. I'm not too sure if it is available that day especially it's hard to get them on late afternoon which is the time I went to, because of luck I got what I've wanted, the shop save those scraps and store in the freezer. The "whiting fish heads" for crabbing baits.
Before I've left the shop, I took a business card in case I needed some whiting heads again in the future, although they're 5 minutes drive only it's still best to call them ahead of time before going there just checking if the product I've wanted is available on hand so then I can place an order. It's just convenient and I'm avoiding to waste some time.