Best practices is to put a fuse if there is a risk to catch fire.
The whole idea of having a fuse is to protect against fire when things go wrong in unpredictable ways, so relying on the power supply protections is not good enough.
Also, the "not my fault" approach if the customer uses a wrong power adapter will still hurt your product badly. If a single unit will catch fire, no matter the reason, people will find out and avoid your product(s) in the future or, someone else might make a product review and point out your product can set the house on fire. Not good for business.
As an example, PC motherboards (DC powered) have fuses for the external connectors that carry enough power.