Do most places allow this proxy card without owning the actual card these days? Back when I played in 93-97 you could use proxy cards, but it was usually a land card marked with an indicator of the real card, and the person had to pull out their real card (usually in a plastic case) to show they actually had it (and show the stats).

I had a friend with a color printer that tried to make counterfeit cards to use as proxies (not to try and sell, the printer he had back then was not very good), he got caught at a game night at a shop (unofficial tournament) and was actually banned from there.