I've never used a Mary Kay product in my life. I prefer Avon and Shain Dee. The more this person SPAMs the forum, the less inclined I am to use Mary Kay.

i already tried to address the issue. it's just one woman who works for them.

We have no connection with Mary Kay and I'm not certain which discussions you are refering to.  Please direct me to them.
There is nothing special about Mary Kay that makes them better than most any other products you can buy in your local grocery store.

To play peacemaker--and granted I am new-ish here--maybe she is just talking about what she knows. I think everyone recommends what they know and like, and I'm guessing she knows and likes Mary Kay products. It isn't as though she can make any money from people here purchasing the products (unless the idea is that they would mail order them from her...).

All of her posts read like a sales pitch. It's hard not to be suspicious when her solution for every question that gets posted just happens to be a Mary Kay product.

She's likely trying to generate some sales but she also may sincerely believe in the products she pushes.  (I would hope so!) 
It's a little more refereshing than some of the companies I've worked at where the people in charge of Marketing were too good to use the products they were selling.  It never ceased to amaze me.  They believed the marketing hype of their competitors even though they knew their own marketing was mostly exaggerations. 
But if it gets to be too much, we'll address the issue.