In the teaching world, the pitch isn't about the supplier at all. It's about the customer... the best sales conversations present the customer with a compelling story about their business first, teach them something new, and then lead to their differentiators. Don't lead with [a solution], lead to [a solution] (Dixon/Adamson p. 74).
Yes, non-profits need to have a marketing strategy – not the dark arts kind of marketing, but the capital M kind of marketing. If you're an executive with a non-profit you need to define the audience with whom you want to connect, work to understand their needs, and leverage your strengths to meet those needs better than anyone else. That's marketing.