A customer pitch and an investor pitch are two very different things. Sometimes almost opposite. E.g. to customers you'd want to emphasize how low your prices are, whereas to investors you'd want to emphasize how big your margins are.
But when the investors do happen to be typical customers, you can give them the customer pitch as well. If they leave the meeting wanting to buy the product, they'll believe everyone will. In fact if anything they tend to overweight such evidence.
Another way to understand the difference: an investor pitch is a customer pitch where the product is your stock.
