I responded the way I did because what you said wasn't really a rebuttal but a turn of conversation to a different situation entirely and warranted a "yeah,, cool, man. You sure got me!" response.
A (real) beard, a moustache, a goatee etc are all well groomed, planned, and traditional styles. For better or worse, in the eyes of many old people stubble does not really fit this category even if we as young people think it's fine.
A 30 year old interviewing with a goatee or moustache gets viewed as someone that has probably had that facial hair for a long time and it's their adult look and is professional. A person with stubble is not necessarily viewed that way, right or wrong. That's the world. Does it matter? Maybe not but shaving 1 day to avoid that stubble look makes sense It's all about minimizing subconscious perceptions by programs. It's not the same as saying "if these people don't like my brown hair then I'm glad they didn't choose me."
Also, I meant what I said about it being awesome you have a goatee while applying for psych. Dope!