Movie/TV deals are the modern version of old-school political autobiography money laundering.
Political donations are limited. No FEC/SEC limits or tracking on book purchases. Have an autobiographical soft-serve pulp piece ghost written, then slap $59.95 on a hardback version that costs maybe five or six bucks to print. Donors can direct-buy them by the caseload, sometimes by the truckload. Distribution to actual bookstore is just icing on the cake. It's a legal way for large donors to funnel money without running afoul of election or donation laws. Move/TV deals are more of the same, only this time with money shown as an investment in the show's production company.
Six-figure-plus speaking fees are another way. Donor sponsors a speaking engagement. Sponsorship goes to the entity holding the event and not to the speaker so it's considered a marketing or "community investment" expense. Sometimes it's a double-dip for donors as many of these engagements are produced by supposedly "non-profit" organizations. Their candidate of choice gets a big check, the donor gets a direct tax write off.
Brad