Reddit has millions of viewers. Reddiquette says not to complain about them. Reddit's millions of viewers can't simultaneously keep track of every post. So, if they're spaced out by a fair amount of time (3-6 months and above) then I don't see an issue. A repost should be flattery to the original source of the content, meaning it was so good that a user risks an onslaught of hateful users just to share content to a new audience. Reposts are good. Viewing content is what reddit is about. Viewing good content is the point of the voting system.