I suppose you could send a dollar's worth to a different address and hopefully they'd get the hint.
Firstly, if that key is put there intentionally for someone to get their hand on that key, and if that kinda seems sketchy, then I will avoid dealing with that key entirely. This is just the first step for you to get scammed. The moment you put that key in, there are some scenarios that are going to happen.
You may get hacked immediately after putting that key in your device.
Your other wallets (if logged in, in the same device) might get hacked.
Your wallet will may get controlled by BOT, in this case every token or valuable coins available in your other account may get transferred to a totally unknown wallet controlled by hacker.
There were a scam recently where scammer send fake stable coin into wallet and when they tried to transfer that stable coin, hacked had taken the control over his wallet.
If not sketchy, then I will keep them. Call me greedy, but whom can I find with this piece of paper that has nothing about them and no way to trace them from a wallet address.
So beware of scammers and keep your assets safe.