Incense and Bath Salt Intoxicants

I've been hearing about kids ingesting bath salts and incense to get high for the past year.  I had never heard of this before.  These synthetic legal intoxicating drugs (SLIDs) have come on the scene and have increased in popularity.  Who would want to snort bath salts or smoke incense?   What the heck are these things?

Although they are sold as bath salts and incense to avoid FDA regulation