We have a car dealer around here with an ad that reads "No Fake Lures". Now, as I understand the concept of a lure, if it doesn't attract attention, it's not a lure. And if a lure does attract attention, it's a lure, so no matter what is used to make the fake lure, it's a an actual lure. Therefore, it's not possible to have a fake lure. What do you call a statement like "No fake lures"?
From OP's perspective a fake lure is presumably an oxymoron - a figure of speech that combines contradictory terms.
I can't say I agree though. Suppose the dealership has a sign saying "Up to 90% off", but in fact no prices are reduced by more than 10%. The dealer might say "Ah, but we did have a car a few years ago that we sold for 90% less than the original (unrealistically high) asking price". I would say that particular "lure" was "fake", in that it was misleading.
So really, I just think OP has adopted a narrow and unhelpful definition of "lure" in this context.
You could say that this phrase is tautologous, since all lures are fake and therefore the use of the adjective "fake" adds nothing. Tautology is often used as a literary device for emphasis, but here it is just a poorly expressed idea. However, as the previous answerer pointed out, this assumes that all lures are fake.
I'd say this is merely an epithet, not oxymoron, not tautology. Lures can be fake or real.
Imagine the salon carries a Ferrari for $100k. Seems like a bargain, right? Situation 1: Under scrutiny, it appears to be all rust, ruin and junk barely painted on the outside. You won't buy the piece of junk even if you could afford it, no way! But you're already there, you may have a look at other cars. This is a fake lure, it attracted you to visit, seemed to be very attractive but appeared to be crap.
Situation 2: The car is in mint condition, and the price is very attractive, even if still out of range of most customers. People will come to see it, take it for a test drive, then buy a more affordable car. The car is definitely a lure, attracting many customers, but it's also a real bargain.
So in this case, the sign means: everything is worth its price, and you won't be ripped off buying attractive-looking junk.