My main objection would be about the game itself, if the rare items are just vanity pieces or especially illustrative and elaborate items of artwork then its fair enough the game continues and one player looks nicer aesthetically then another but overall its still about skill in the game itself.
If ever the game items distribute power and advantage over other players and thats done through monetary reward then it becomes a problem that will ultimately reduce gameplay and fairness. We'll get one section of players from a rich country with an advantage over players from a poorer country and now you just have a game that mirrors the rather unfortunate realities of normal life that some are richer and thats not really a proper game or one I'd want to be part of personally.
Fifa in the example above gives advantage to those with alot of money. Maybe a really great player can overcome their disadvantage but its not a level playing field, the poorer person has weights put on their back to stop them competing as well vs the richer person. Thats like the mindset of a hundred years ago, EA in general are not of my favorite companies because of this policy and similar ideas they keep repeating this theme.
This is a common problem in games where the gameplay depends on the injection of money. Usually, sooner or later, they turn into pay2win game. The only games that I love from this genre are collectible games - the logic of pay and win there is quite reasonable. But to be honest, I love these games not because of the gameplay, but because of the opportunity to make money on them