When creating your vine listing, it asks you for the value of the product. Don’t put your sales price, put the wholesale price (the price it costs you) down, or even lower!
Because US Vine members pay taxes on the values which you enter and they can’t clip any coupons! It adds up and they will pass on your product!
Example: When you add your sales price as the value $60, and have a clippable coupon $20. The vine member thinks “why should I pay taxes for the amount of $60, if it costs $40 for the public” and when your competitor has its product listed as well with less tax value, that product will be gone faster than yours.
Vine members can order up to 8 products a day, and the tax value can bring them into a different tax bracket, that’s why they are very careful with it.