Hello all,
I just finished a MSP>AMS flight DL 264 which I originally had EC seating on. When I arrived to the airport to check in, I was moved back to row 23 which was no longer in EC seating. I'm wondering if I have a case for compensation or if I should just deal with it. Please consider the following:

Checked in, and the DL worker gave me my ticket for row 23. I said immediately that I previously had an EC seat. I explained that I bought the ticket weeks ago and immediately logged into change my seating for the free upgrade to EC. She asked me to show some kind of email or proof, but the emails that go (as a receipt) out have the original seat assignment. Since she already checked me, she couldn't see what was before that, and neither could I. I was in 14 or 15, and I know I'm not crazy because my flight home still has the EC seating selected. She said to speak to the GA.

At the gate, the entire coach cabin was full, and three people were cleared from standby. I noticed one individual was cleared from standby right into EC. I also noticed that 7 BE seats were unclaimed. Obviously, I'm aware that BE upgrades only happen when you're lucky enough to be on an overbooked flight, so I wasn't expecting a BE upgrade, but I can't figure out why I was "downgraded" rather than upgraded. It turns out the woman who sat next to me was also moved around.

Do I have a case to request some form of compensation? I realize I'm arguing about a free upgrade, but I think it's poor form that they've moved me without any notice. I would have paid the fee had I known I was going to be moved. If they would have sent an email that there was a seating or plane change, I could have been prepared.

TL;DR
Got bumped from EC to regular coach seat.
Plane was full, and a stand-by flyer was placed into EC (why not a reg coach seat?)
I want something out of it. Am I being too greedy or do I have a case?

I realize loyalty holds no weight with Delta these days, but lately I'm flying Delta internationally every 2-3 weeks for ~$1200 a ticket when I could easily go with United for $800. I may have to make the change.