... and they will flee. If those who provide services are charged more, they will pass those costs to the students. If the students are forced to pay more, they'll do their online ordering on free wifi at the coffee shop, (and look for a cheaper place to live). By providing network access, you are providing a useful service that enhances the appeal of you rentals. Diminish the quality or value of that service, and you diminish the value of your rental.
/* Halley */ (Halley's comment.)