As a buyer, if your product is quality, and its not a hassle to arrange pick, ect; you need to be within $0.50/lbs of market going rate on ground; maybe a $1. Thats assuming good product. Ive seen some direct sales places that the quality is just really varied on fat content, or flavor. Other direct sales operations, the pick up/order/payment is just plain a turn off...
Edit: Even the packaging. For us, 1.5lbs individual tubes is great; for others, they want 1.0 lbs or 0.75 lbs at a time depending on the house old. Even one i like, 1 Friday per month, 5-7pm, for pick-up, often makes it not worth the trouble.
Also, just giving one person's view, some people may be willing to pay 50% higher than market, just not me. If you are selling out quickly, it sounds like a price increase is in order. Sams Club is right around $6/lbs; so you should be charging $6.50-7/lbs IMO