Valuing something contributes to the economy per se
We conventionally take it that someone has contributed to the economy when they provide a service that someone else values positively. This is correct. But notice there are two sides to this transaction: the provision of the service and the valuing of the service. If no one valued the service, then providing it would not be valuable and would not contribute to the economy. In a causal sense, then, the provider and the valuer are coequal contributors to the economy: each's contribution is a necessary condition for the other's. Note that it is not by paying that the valuer contributes to the economy (except indirectly insofar as the payment induces the provision of the service). Rather, it is the valuing itself that causally contributes by being a necessary condition for for the provision to contribute.