I made this transaction:
662f7e90b1e3d6f55c06388c07b62e15c6ab672c936372b64e8748c22d3923fb (game purchase on indiegala)

And it had a really hard time getting into a block even tough paying like 0.0004 in fee. Sites listed it like miners didn't want this transaction.

Then I did this transaction:
f3cb81d3a01f03b4e3b473fd3d264d0661d31f9081ca8ec6c544fee08b4ef853 (purchase of 100€ Steam gift card on bitrefill)

and this time, even when paying LESS in fee - 0.00032649 - it got pretty quick into a block and some sites listed it as a preferable transaction for miners.


What causes this?