Yes, it would be morally wrong to take stuffed animals or any objects, and put them in store display microwaves and toaster ovens (or any real appliances) for several reasons:
Destruction of property: Intentionally damaging or destroying someone else's property is unethical. Store display items are meant for showcasing and advertising products, not for misuse or destruction.
Disrespect for others: Performing such actions shows disrespect for the property owners, store employees, and potential customers who may find it distressing or offensive.
Animal cruelty: Using stuffed animals in this manner could be seen as a form of symbolic animal cruelty, as they often represent animals that children love and cherish.
Negative impact on others: Witnessing such actions might disturb or upset other people who come across them, leading to negative emotional consequences.
Legal consequences: Engaging in destructive behavior may also lead to legal consequences, such as being charged with vandalism or destruction of property.
It's important to treat public spaces, objects, and other people's belongings with respect and consideration. If you have any creative or playful ideas, it's best to find harmless and respectful ways to express yourself without causing harm or distress to others or their property.