It seems my postcards are consistently scratched/scuffed on the face of the card when mailed from the US. Does anybody know why? I am assuming it is from the machines that sort the mail, but you would think they could make them so they didn’t damage mail.
Is there anything I can do to prevent this, aside from mailing the card in an envelope?
Thanks.
Since USPS operations are 99% automated, there is little you can do. One possible solution is to ask the sender to hand the card to the counter clerk to hand-cancel the card.
The sorting machines can be very abrasive. Even if you have a clerk cancel the stamp they still run it through their machines. If you’re concerned about your outgoing postcards getting scratched you can always put them in clear postcard-size sleeves.
I live in the U.S. and have the same problem with the postcards I receive - not all of them but probably about 25%. When I send cards, I often send them in envelopes, especially as the postage for international postcards and letters is the same.
Take a look at this USPS video - hard to believe that most postcards make it through these machines
May have to pay non-machineable postage for sleeves though 
No way to avoid this but sending in an envelope would help.
Cover the front side with paper and washi tape. It protects your front side.
Am I the only person who actually enjoys the scuff marks and dents and other travel scars?
I’ve seen this happen on a good number of my postcards. The scuffs all depend on your local postal processing plant and the sorting machines and maintenance on them. I’m pretty happy that my local plant seems to take pretty good care of their machines and occasionally have even hand-canceled my incoming international postcards. Here’s a few articles that can help provide context.
“If your local USPS post office sorting machines are not calibrated correctly they can penetrate the postcard’s paper and color toner leaving black smudges, burn marks, scuffing, rub marks, tears, and/or even rips” Quantum Postcards
“If the roller applies too much pressure as it grips the mail, it may penetrate the color toner and UV coating on the surface of the postcard, leaving scuff marks.” Click2Mail
Nope! I’d miss the marks and dents and even the smeary postmarks!
Every postcard I’ve received has a scuff mark right in the middle of the card. Sometimes it’s just the glossy coating, but sometimes it scrapes off a bit of the image. The USPS sorting machines are impressive and can process a ton of mail per day and read terribly written addresses, but they aren’t very gentle.
Recently I received a letter with a wax seal on the back and several postcards on the same day. It looks like the letter ended up going though the sorting machine, and the machine took a chunk out of the wax seal and smeared the wax across one of my postcards. Luckily I was able to peel the wax off without damaging the card.
I’ve decided to just embrace the scuff marks. They add character!
The USPS sorting machines are enchanted cookie monsters and they regard the cards as cookies! 