You're right - Delegating is different than renting in the sense that I won't get any returns or profits (it is absolutely free)
But it is pretty similar to renting in a lot of ways - I still am the owner. Collection power goes to the person I delegate a card to. I can take the card back anytime.

In this particular giveaway, my aim isn't direct profiting off of my cards. Simply more exposure, and giving an opportunity to Splinterlands newbies to try these cards for a season before making a future purchase decision.