Matt Stafford -- JUST DID IT ... Nike Giveaway At Wedding Bash

Matt Stafford is officially a married man -- tying the knot with longtime girlfriend Kelly Hall ... and every single guest got a FREE PAIR OF NIKES!!!!

The two got married in a lavish ceremony in Atlanta on Saturday night -- in front of friends, family members and several Detroit Lions teammates including Golden Tate (pictured below) and Joe Fauria (above left).

But the coolest part (besides the couple getting married) ... was the wedding swag -- a free pair of Nikes to every guest and a custom airbrushed trucker hat for all.

At the end of the night, the couple got into what appeared to be a vintage Rolls-Royce ... and well, you know what happens next -- TOUCHDOWN!!!

Mazel!