Tate, 27, may have thought the photo way a harmless way of supporting her hometown team, but it apparently rubbed some diehard Seahawks fans the wrong way.
One such fan was Stephanie "Snowflake" Eggink, the XFC strawweight champion.
Eggink, 25, was so annoyed by Tate sporting a Seahawks t-shirt that she took to Facebook to call her out for basically being a poser.
"I bet she knows absolutely nothing about the Seahawks or football in general," Eggink said of Tate on Facebook. "I however, am the real 12th man."
Does Eggink have legitimate reason to be bothered by Tate's Seahawks fandom?
That all depends who you would ask, but there's no denying that Eggink herself is a passionate Seahawks fan.
"Snowflake" eats, sleeps and breaths Seahawks football, and she even predicted a Super Bowl berth from the team during a radio interview last August.
"Let's just say when the Seahawks play the Vikings, me and Shayna don't speak for about 48 hours," Eggink said in a somewhat joking manner when asked about her football allegiances. "We're big football fans. Actually this year the Seahawks have like four ex-Vikings players on their roster, so it's an extra special season.
"Mark my words. The Seahawks are going to go to the Super Bowl this year. I'll put money on that."
As for Tate, she did go on record last September saying she hopes to raise the Seahawks' 12th man flag at some point during the 2013-14 season.
Analysis: Even if Eggink is more of a passionate, diehard Seahawks fan than Tate, there's nothing wrong with "Cupcake" showing a little pride in her hometown.
Tate is a native of Washington, so all she was doing by sporting a Seahawks t-shirt on Instagram was giving a little support to her home state.
In all likelihood, Eggink knows more about the Seahawks than Tate. However, Tate deserves props for at least sticking with one team and not being a flip-flopper like other celebrities.