Discover sent out an offer by email. After you activate it, if you join Sam's Club ($45 membership) and check out with this Discover card, you get the $45 cash back provided by Discover, which is basically free. Plus, combined with Sam's Club's own gift card offer, you can get another $45.
After activation, Discover only says to use the card for checkout; it does not say you must use the link below.
So I personally think it should be stackable with the current Sam's Club offer, for example:
- Sam's Club $45 for $45 gift card offer（https://samsclub.official-coupons.com/?ppcid=9&keyword=%2Bsams%20%2Bclub%20%2Boffer-NATIONAL）
- Note: If you want to be safe, you can first enter through the Discover activation link you were given, then copy and paste the offer link above into the address bar.
In summary, Discover gives you a free membership, and Sam's Club gives you a $45 gift card in return. Plus, Sam's Club gift cards can be used at Walmart, so they’re still very easy to redeem.