The day changes the answer
Seven occasions, seven different problems.
The same gift is right for one of these and wrong for another. Christmas is decided by the delivery deadline. A birthday has no deadline at all, so it is decided by fit. A first Father’s Day is a milestone. Grandad has spent decades getting rid of things. These are not the same brief.
Pick the day
Each page orders its products by the constraint that actually binds on that day, and says so above the grid. None of them orders by commission.
Father’s DayFirst Sunday in September in Australia.339 giftsChristmasThe one where the delivery deadline actually bites.339 giftsA birthdayNo fixed deadline, so you can choose properly.339 giftsFirst Father’s DayNew to the job, short on sleep, long on pride.116 giftsA new dadGive dad something that is about him, not the baby.116 giftsGrandadHe genuinely does not need anything. That is the puzzle.196 giftsA father figureStepdad, uncle, mentor, the bloke who showed up.175 gifts
Australian dates, not northern ones
Father’s Day in Australia is the first Sunday in September, which is spring and well clear of the Christmas freight crush. Christmas is the one where the post network is under real strain and the deadline decides what you can buy at all. The delivery clock on this site counts business days against both.