As long as it's clearly labeled a repro I do not see the problem.
This is the most important part to me as well. It genuinely bothers/scares me that there are repros out there that are not marked as such.
While I don't ever see myself purchasing a repro of a game that had a commercial release, I do own a repro of The Legend of Zelda: Ancient Stone Tablets and absolutely love it. I could have emulated it just fine (and I have and continue to do so with other games), but it is such a cool collector's piece and I love having it on my shelf.
If you don't care about having individual physical carts and are interested in a lot of expensive games I would definitely recommend a flash cart. I have never owned one, but I have heard many great things about them and you still get to experience the game on the original hardware.
On a sidenote, we are pretty relaxed on rules here, but watch the language in the thread. Homophobic slurs are completely uncalled for