You've just answered your own question. If there is no difference, there is no truth in advertising issue, sot he FTC won't do anything. Whether there is a difference or not, I really can't say and I don't avoid GMO myself, and not preachy about GMO.
My concern is the the fact that some people ARE concerned, and simply have the right to know if itis GMO or not. The controversy and lack of long term science means people have the right to choose, but can only do so if they have information. Technically, that is what the FTC should be fore, but they tend to be spineless when it comes to stuff like this.