Everyone is not meant to manage.... or sell.
The typical path to higher earnings is through promotion which, at some point, means managing people and, in some situations, responsibility for bringing in business. This is a common practice in professional service firms (law, accounting, engineers, etc). Some law firms are now limiting the number of full partners, but rather than losing good lawyers because of the "up or out" policy they are naming "permanent associates", who do not have the "business development" (eg sales) responsibility of the partners. Compensation can include profit participation - no law says otherwise :-). These permanent associates may not make as much money, but they are also working in a setting that works best for both the individual and the firm.
In your own organization, compensation - ideally - has a relationship to the value that the individual brings to the firm. Titles, as an aside, cost nothing. In my academic settings, one university would give their adjunct instructors a rank - "lecturer" - and an annual faculty appointment. "Lecturer" sounds better to the outside world than "adjunct", doesn't it? :-) The cost - zilch. But it means a lot to me. Companies will create ranks within the same basic job title - "junior", "senior", and so on - gradations that may reflect experience and competence, but the job is essentially the same.
The takeaway - think about creating career ladders that recognize and reward expertise, and retain folks who don't want to manage - and shouldn't manage - but have so much to contribute to the firm. And compensate them - and get creative. Such employees may be interested in being sent to conferences, a sabbatical, or opportunities to pursue an idea to see if there is potential. In the end, it's all about the talent.