Because you should have 2fa set up and your access to AWS accounts should expire after 1 hour. Also, you likely have full disk encryption enabled, and the person stealing your laptop is unlikely to know who you work for and are more interested in selling it.
If someone acquires credentials, they are usually multi use and long term. And it can go unnoticed if an ec2 instance is span up running crypto mining on your dime, only for you to notice at the end of the day that your estimated bill has shot through the roof
