Thanks for your questions “Do fast food restaurants or cafes within or very near to college campuses ever close for lack of business?”
I think this questions restaurants or cafes is very important for all like yours. Here I’m trying to give your answers in brief.

There are other factors to consider, too.

Assuming you lease the building instead of owning it, your landlord might become greedy and raise the lease or refuse to renew because they got a better offer or want to redevelop. (San Jose, I’m looking at your landlords.)

During school breaks, you’ll have drastically less business. Some restaurants in Arcata closed during the summer because half the population went home for the summer. How will you budget to pay your rent and whatever minimum costs for staying in the building and/or staying open but having less income?

Economic factors may affect your patrons’ budgets. Tuition hikes may lead to more students eating ramen and homemade PB&J. Partial furloughs at Humboldt State hit the restaurants first because faculty and staff had less disposable income.

I’ve definitely seen empty restaurant spaces in college towns: Arcata, Berkeley, Irvine, San Jose.
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