I’ve never even considered looking at the date somebody joined when making a purchase. And surely even if there are those that do, they’d look at the upload date of the item, rather than the joining date of the author?
And I like Sprite more than I like Coke, even though Coke sells a lot more. I’ve never let the sales figures of Coke influence or lessen my desire for Sprite. Not that I drink a lot of it, it’s not very healthy, but it makes a nice mixer for other unhealthy drinks.