MLM Businesses mainly focus on consumable items. This includes healthcare and nutrition products, cosmetics, consumer durables, etc. Since these are the most common items purchased, selling them becomes easier and more profitable. And since they are consumable, customers and distributors will use up the products each month and then need to place a new order. This creates residual income.
Other MLM Companies specialize in utilities, juices, legal services, travel, phone plans, gold, silver and countless other items. If you can think of an item, its probably sold in at least one network marketing company.