Primer substitution. Yay or Nay?

Before you think I've gone absolutely mad, please bare with me.

So I've been hearing about the similarities between some of the top primers (Smashbox, MAC, Sephora) and...

this little number

Monistat Chafing Relief Powder Gel. Yes, you read that right. 

I know it sounds disgusting to put this on your face, but I've read countless reviews and watched many YouTube videos from top make up artists explaining that the ingredients are the exact same. 

These well known primers run anywhere from $20-$50 and at only $6 this make up secret is sounding more enticing by the minute. Did I mention that you get more than double the product? 

The only downside is people having to see it in your make up bag. 

Problem solved.

Have you ladies heard about this before or did I just absolutely mortify you? Any thoughts are appreciated :)