Gift cards do bring people into the shop, here are some ideas to get more people to come to the shop using gift cards.
1) Instead of giving a local charity money for a donation, what about giving them a gift card that can be redeemed in your shop? Someone from the charity will come back to redeem the gift card, and maybe they will buy more too.
2) Instead of offering your customers a discount on the item they purchased, what about offering them credit on a gift card that can be used on their next visit.
3) If someone buys a large gift card in your shop, what some shops do is offer a bit of a concession say 5% off for a sizable purchase. A better idea is to give the buyer a smaller gift card rather then a discount. This means that recipient of the big gift card will come, and the small gift card will bring the buyer back into the shop.
An observation that is commonly noted by people who sell gift cards is over 70% of people will spend more on a transaction than the value of their gift card.