One of the great aspects of digital media is how easy they are to give away to people. If you want to buy someone a Kindle e-book, Amazon makes it very easy to email it right to them. Likewise, video game maker and distributor Valve frequently runs sales on Steam, which allow people to buy games cheaply and send them cheaply to friends.

But one thing digital goods have that physical goods don’t is the ability to prevent them from being sent as gifts. Valve has exercised this option for its game Counter-Strike: Global Offensive, which is currently on sale for $7.49—50% off the list price of $14.99. While you can buy a copy for yourself, you can’t buy and gift one to a friend, or keep one on hand for later gifting.

A Valve representative said on Reddit that they want to “grow the community” with the sale, and the only players who tend to stick around are the ones who buy the game for themselves. But a couple of the other comments below that one seem to offer more likely rationales—it will prevent cheaters from stacking inventories full of “gifts” they can use later on themselves after their current account gets banned, and it also prevents people from buying up cheap copies to resell for a profit after the sale has ended.

Given that, unlike Valve games, you can’t retransfer an Amazon e-book once you buy it or gift it to someone, those rationales would be less meaningful for restricting an e-book—but still, it’s a reminder that it would be possible for Amazon to limit rights such as gift-giving or lending with specific titles. It’s not clear why they might want to, but they could. Likewise, I strongly doubt Valve will eliminate gift-giving rights for most titles it puts on sale unless there’s an ulterior motive like cutting down on cheating, simply because gift-purchase money spends just as well as self-purchase money, and people like being able to share cheap games with their friends.

Of course, you can only gift or re-gift Valve video games at all because Valve chooses to let you. Likewise, you can only give Kindle e-books as gifts because Amazon lets you. (It didn’t used to.) Digital goods simply don’t get the same first-sale rights as physical goods, and that’s one of the tradeoffs we make when we decide to purchase them. Digital first sale is a contentious issue (as demonstrated by congressional hearings looking into that matter) that probably won’t be settled any time soon.

As such, it’s worth taking note whenever a company alters the rights it gives its customers, even on a small scale. It could have implications down the road.