Compensation is very limited as to benefits, no job sercurity (contract or part time mostly, rarely do people become permanent). Not much room for growth (if any).
The position of "product knowledge" or "Brand Ambassador" is to know what the customers needs are then fulfill them by other if your client's product. Thing is: you better sell! Programs are rated of their success by the numbers, so the bottom line is still the most important thing. Even if you know this, the idea of commission or an incentive is always brushed off by management.