Buy $50 Grubhub GC, Get bonus $10 GC

Grubhub has a Mother’s day offer to buy $50 in Grubhub gift cards and you’ll get a bonus $10 Grubhub gift card free.
I sent a digital $50 card to myself, received both it and the bonus $10 GC in my email almost immediately. Added both to my account. No problems at all.
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