As mentioned by the last poster, it's pretty standard for a store not to sell you a gift card for a gift card. But you already mentioned going in the right direction...assuming you will always PIF, turning non-bonus category spend into bonus category spend is a good play. If you were going to spend $30 at Olive Garden...why take 1% or 1x when you can get 5% or 5x by using the appropriate card to purchase gift cards from Lowe's. You should always look for these opportunities (just always PIF and don't stock up on gift cards if you wouldn't have spent that money at the specific retailer anyways). Also remember though, this is risky as what if you buy a Lowe's gift card from Publix for 6% cash back with the AMEX BCP, but then Home Depot runs a 50% off tile sale--you're stuck with Lowe's gift cards...and in this case...unless you can afford to float that money even longer...you're loosing money.
Something to contrast to buying gift cards at retailers is being resold gift cards from places like Plastic Jungle or Cardpool. I've had great success getting 5% to 16% immediate cashback (discount on the purchase itself) in non-bonus spend for all kinds of unavoidable charges (like pet food, home repairs, glasses). Just some thoughts--save the Sony pts for something else.
