The truth was that Percy had arrived home on Tuesday, the day of Penny's birthday, and technically speaking he could've given her gift before today. Besides suspecting an owl would have a difficult time carrying his present to Penny, Percy chose to wait until George's birthday party for 'political' reasons, again hoping to avoid Penny as much as possible for the time being. Even the phrase, 'I'm glad to see you', was spoken not necessarily because he was glad to see Penny, but because he was glad that he could give her the gift. The hug and kiss on the cheek was accepted awkwardly, and irritated Percy, who concluded that Penny had no consideration or respect for his feelings after he thought he'd made it quite clear that he rather would keep their physical contact to a minimum.
He hastened to cover his irritation with strange smile, and said, "The instructions may be read by an advanced Translation Charm. The beans are the nation's highest quality." Yes, just like with Hermione, a modicum of pride reflected in his voice for choosing such a perfectly matched gift. Now he only hoped George would appreciate his present just as much.