Channels, used in the context here can refer to the various segments of a corporate department or they could be resellers of the same product. If one channel undercuts another, to make more money, the ensuing conflict means the product owner, customers and employees themselves may suffer.
For example…
Let’s say a cosmetics company has gone all out and employed door-to-door, online and telephone based sales people. If the telephone-based team isn’t making as much money as the online team, they may try to dissuade their customers who are interested in buying online, spread rumours about the security of online transactions and other such underhanded approaches. Channel conflicts are not so pleasant for anyone!