AFAIK
Walmart and Sam's GC are interchangeable. On the back of every card I have from either it lists Sam's , Sam's.com, WM, WM .com as eligible. I just used a bunch of Sam's club issued GC and eGC at Walmart. I've used Walmart GC and eGC in the past. If I look on walmart .com for both GC they both state
- Gift Cards may be redeemed at Walmart stores, Walmart.com, Sam's Club, and Samsclub.com by SAM's Club members.
So going into a Walmart and buying whatever they have on the shelf should avoid any activation issues.
Where I'm more concerned is if you can use a GC to pay through Sam's Club for the tickets. Have you started a checkout and it gave the option? I see the tickets through the Travel & Entertainment service which the FAQ for that states no GC. And going through a dummy booking is only giving me credit/debit options.
https://serviceshub.samsclub.com/pages.php?sub=tawfaq
What are my payment options?
We accept all major credit cards including Visa, MasterCard, Discover and American Express. We do accept Sam's Club Mastercard.
We currently are not able to accept gift cards and other private label cards including Sam's Club PLCC. We also do not accept Travelers Cheques or Personal Checks. All payments are in USD.
(emphasis is mine)
Is there somewhere else to buy the ticket at Sam's Club that lets you use a GC?