Is paying for forbidden movies less sinful than obtaining them for free? And if it is stated in books of Fiqh, "It is forbidden to sell such-and-such," does it refer to both buying and selling, or to selling only?

It is forbidden to watch, sell, buy, possess, or gift forbidden films. They must be destroyed or erased. It is not permissible to pay money to watch these films, and wasting money on anything other than obedience to Allah is forbidden. It is not permissible to obtain these films through theft. What is forbidden to sell is forbidden to buy, because if Allah forbids something, He forbids its price. The principle is that anything whose use is forbidden, its sale and consumption of its price are also forbidden, and there is no difference in all of this between selling and buying.