If you Set this card and it is later destroyed, this may make your opponent reluctant to destroy your Set Spell/Trap Cards later in the Duel.
This can be very useful in an Exodia deck. Because of wording used in this card, your opponent not only won't want to destroy your Set S/T Cards, he/she might have second thoughts about sending cards from your hand with cards like Evilswarm Ouroboros or Stellarknight Triverr. This is very useful to protect any Exodia limbs you might have in your hand.
Your opponent's use of "Vain Betrayer" can be their downfall. If that card is face-up long enough, it will Mill every (remaining) copy of "Jackpot 7", resulting in your victory.
Activate "Hippo Carnival" after you give "Burglars" to your opponent to special summon 3 Hippo Tokens to attack Burglars, allowing you to send all 3 copies of this card to your graveyard and win the duel.
Alternatively, you can activate "Scapegoat" during your opponent's turn, then switch 3 of the 4 sheep tokens to attack position on your turn and attack Burglars with them to win the duel.
You can also summon "Summoner Monk" and use his effect to special summon "Dark Scorpion Burglars" in Attack Position. Next you can play "Double Summon" to Normal Summon a weak low-ATK monster that can special summon another weak monster from the Deck when they're destroyed, or activate the aforementioned "Hippo Carnival". Then give "Dark Scorpion Burglars" to your opponent and attack him 3 times to win.
Setting this card in a "Fire Fist" deck is both hilarious and effective. Your opponent will be naturally inclined to destroy your facedown cards for fear of them being "Fire Formations," and may even try to use "Malevolent Catastrophe." This card will both dissuade them from doing so and possibly even earn you an instant win.
Wait until you draw all three "Jackpot 7" cards, set them onto the field simultaneously, which will increase the speed of your opponent destroying them all as opposed to letting them do so one by one.
With this card in your hand, give control of a face-down "Morphing Jar" to your opponent through a card like "Creature Swap". When it is flipped, the effect of this card will trigger. If you manage to gather all 3 copies of this card to your hand before pulling this off, you will win the Duel.
In a Deck with extremely few monsters, give control of a face-down "Morphing Jar #2" to your opponent. When it is flipped while you control at least one monster, its effect will very likely send almost your entire Deck to the Graveyard, including 3 copies of this card, allowing you to win the Duel.
As a counter against certain Decks
Use against an "Artifact" Deck as most run "Malevolent Catastrophe" to get off their own effects. At that time, any copies of this card you may have Set will trigger; if you have 3 of them, then you win the Duel.
Use against a "Vampire" Deck, as their effects send cards from the opponent's Deck to the Graveyard.
Specifically, send a copy of this card when your opponent declares Spell Cards for their monsters' effects. This will discourage your opponent from declaring Spells later in the Duel, which is useful as many "Vampire" Decks are weak against strong Spell Cards like "Dark Hole".
This card is useful against "Evigishki Tetrogre" as the opponent often use "Gishki Aquamirror" to bypass the cost of sending spell card to graveyard by returning it to deck and recycle their ritual monster.
Use a destruction card like "Dark Hole" to destroy Nephthys and trigger its effect, then Set as many copies of this card as you can, forcing your opponent to destroy them during their own Standby Phase.
Use against a Mill Deck to stop it in it's tracks, as you win when your opponent sends them to your graveyard. If you draw any of these, just activate them to prevent yourself from running out of cards.
This card can instantly stop a Zombie Mill Deck. If your opponent sends one copy of "Jackpot 7" to the Graveyard, they will be encouraged to stop their assault on your Deck.