When I was a director of the black studies program (2007-2013), spoken word poets, or better yet, their managers would contact me and present me with the promotional packages, seeing if I wanted to bring their artist to campus. Of course, we couldn't afford them.
The savvier or simply more experienced poet-performers and managers knew that the best way to get an "in" was through student organizations, who have chances to appeal to student councils for resources. That's by and large how it's been working across the country. Let me pause here and say that I'm not knocking how national spoken word artists seek to earn a living. Many print-based or formal poets participate have approaches too, just a different system and thus approach.
Poet-professors based in university English departments and creative writing programs tend to host (and sometimes pay) poets who have MFA degrees and books with recognized presses, which means spoken word poets are less likely to get invites. The poet-professors also regularly assign the volumes of those "formal" poets in the classes that they teach.
Poets with more friends and the right connections are more likely to get more invites than their peers. And poets with higher cultural capital (which often means poets who've won prestigious awards, published with notable presses, or again, nurtured and attained the right connections) are more likely selected for those campus "writer series."
Like many systems, there tend to a few select big winners and many, many...well, non-winners. Such is the case with spoken word poetry and print-based poetry. Relatively few of the poets are ever in positions to earn livings based solely on their poetry. Many print-based poets earn stable livings through university appointments, and because spoken word poetry has far less resources, many of its practitioners earn livings outside of poetry.
Spoken Word Poetry and the growth of consciousness (in Mississippi)