Is using an inhaler without asthma bad?

No evidence. There is no data on using inhalers in healthy individuals. Studies show an increase in risk of death with higher use of rescue inhalers in asthmatics, but it is likely related to poor asthma control!
Yes. People who use more of the most common inhaler albuterol have an increased risk of death compared to those who use less. There are specific indications for these inhalers. Talk to your doctor.
Not necessarily. Sometimes persistent postinfectious cough may respond to a short course of inhailed albuterol or steroid. Other than that, I don't see a reason to use it.