It will be marked as an expense outgoing to a third party by Disney, and the third party will be named or identified. That third party if did not account for that income and get audited, will be provided a demand letter. Vast majority of the "audits" are fully automated using cross referencing expenses & deductions to incomes.
There is no such thing as "free" when it comes to the US IRS.
There is a clear if unstated expectation that they will receive positive reviews and promotion as a result.