As to the hypothetical situation I suggested of someone who wanted to learn Aikido without taking on the role of uke, perhaps a more interesting poll would be this:
As a student, would you be willing to serve as someone's full-time uke for an entire class. How much would you charge for this service?
As a teacher, would you be willing to accept someone into a regular class on these terms, providing that arrangements have been made for an uke? If not, would you consent to private lessons on the same terms?