newhere,
Thanks for your input and for the מראה מקומות.
Firstly, I never said it was פשוט. Te best argument להתיר might be that it's too prevalent to be an issue of מראית עין, which פוסקים say regarding margarine, but it's far from פשוט (to me) that this would apply to parve cheese.
I haven't seen the כנה''ג yet, so I can't comment on it.
The כו''פ questions the idea that there would be מראית עין in a case where the milk is not really milk (as opposed to where it is milk, but not the type which the תורה referred to). His conclusion is to be מחמיר for meat, but not for chicken (a far cry from “was very strong against this chumra.").
The ש''ך is more מחמיר than the רמ''א and holds it's even a problem on a דרבנן. That would apply to chicken, and also to שלא דרך בישול.
Many אחרונים learn that the רמ''א was only מיקל on a דרבנן when it's בצנעה (which would not be the case in a restaurant). See also פמ''ג who assumes that simple פשט in רמ''א is that by meat, the איסור even applies שלא דרך בישול.
It seems that the only way to be מיקל (besides what I mentioned earlier) would be to hold like the רמ''א, according to how the ש''ך understood him, and not like the ש''ך himself. I don't think the פוסקים take this approach; see בדי השלחן.
Haifagirl,
That case (vegetable burger with cheese) would likely depend on how much it looked like real beef.