If you have more than seven, you will be forced to discard into your graveyard
Rakdos, the Muscle Theft decks built on Threaten effects often employ sacrifice outlets to steal an opponent's creature, attack with it, and then get rid of it before control changes again
A third, and more subtle way, is to run some creature types that are a bit less common that the normal Tribal Deck concept, so you arent leaving behind as many creatures for your foes, but you may not leave behind all of your stuff too
With the right timing, players can collect a ton of treasure and stack up artifacts for their next turn while also damaging their opponent
Keep in mind this isn't restricted to finding basics, so you can use Hunting Wilds to fetch typed non-basics like shocks and Triomes
Factor in whether you're buying to open or to hold before committing