The idea is you use a reseller for all your products, they manage the relationship with the manufacturer or publisher and work to get you the best price/service. If you have doubts about using a "middle man" keep them honest with a 2nd or 3rd quote, sometimes direct every now and then. But working with one rep for all your products can be a huge boon to doing business in savings of money and time.
Disclaimer: I work for a VAR