What practice involves giving excessive discounts for billing advantages?

The practice of giving excessive discounts for billing advantages is best captured by the term "swapping." Swapping typically refers to an informal agreement between two parties where they provide reciprocal benefits, such as exchanging goods or services. In the context of excessive discounts, this can mean that one party may offer substantial discounts or benefits to another in exchange for favorable billing practices or other advantages that are not necessarily aligned with standard pricing models.

Bundling refers to offering multiple products or services together at a combined price, which doesn’t imply excessive discounting for billing purposes. Kickbacks involve getting illicit payments in return for facilitating a deal, typically in a way that is unethical or illegal, but do not directly pertain to the notion of discounts for billing advantages. Cross-selling is the practice of encouraging customers to purchase additional items related to their original choice, which also does not fit with the concept of providing excessive discounts specifically for billing advantages.

Thus, choosing "swapping" indicates a situation where discounts are used as tools to create a billing advantage through an implicit or explicit exchange.