First, how dare you.
Second, I absolutely ran into this at the Disch last year, but in reverse. There was a group of 5-6 seats that were hardly ever used the entire season. During the last series (Florida) there were 3 kids (like 9 years old) that were occupying the empty seats and this frat kid shows up with a couple of sorority girls and immediately is a dick to these kids and tells them to get the fuck out of his seats. They were obviously flummoxed and looked at my group with a "wtf do we do?" reaction. There were a couple of open seats by us and we motioned for them to move there. Meanwhile, I told the frat boy he didn't need to be so aggressive with those kids. He rolled his eyes and ignored me.
Next day, he shows up again, but this time with his dad, who obviously was the season ticket holder (but literally had not shown up for any games until the last series of the season). My dad was with me that game and was occupying one of their group of seats. The frat kid's dad, predictably, had the same dickish attitude and quite rudely said we were in his seats. Had he been cool, I of course would have been like, no problem and moved.
However, I instead asked him "why weren't you sitting in them then?" He only had like 4 people with him, meaning 2 empty seats. So he wasn't even using them, just wanted to exert his ownership of the seats and be an asshole. The frat kid then referenced how I was upset that he made those kids the day before move. I replied, "Yes, you were a complete dick to those small children and there was no need for that. You're just an asshole." He didn't have much to say and I'm glad his dad got to see him called out for it.
Ultimately I of course moved with my dad to a couple of other seats together, but the entitlement was mind blowing.
I hope I see them next season so we can continue the conversation.