I am a 28M and usually I am the guy who stays in the background during social stuff. Last weekend a few of us went over to a former colleague house for a small get together since he just finished a big renovation project on his place. One guy in our circle we can call him Tyler is the kind of person who thinks every house he enters is basically a public park where he can do whatever he wants. He has this annoying habit of treating other people's stuff like its his own property and usually people just let it slide because they dont want to cause a scene during a party. Around midnight Tyler finds this cabinet in the kitchen that was clearly tucked away and pulls out a bottle of whiskey that looked pretty expensive. I was standing right there in the kitchen getting some water and I saw him cracking the seal. I literally told him "man you should probably ask before you open that" but he just waved me off and said it would be fine and that the host wouldnt even notice.
Fast forward about twenty minutes and the host comes in and sees the bottle open on the counter. He looked genuinely upset because apparently it was a gift from his dad for his promotion and he was saving it for a specific occasion. Tyler immediately tries to pivot and says "oh hey man we all thought it was okay to open it to celebrate your new kitchen so we just went for it." He looked at me for backup like we were in some kind of pact. I just stood there for a second and said "actually i told you to leave it alone when you were opening it." The room got real quiet for a second and the host just took the bottle away. Tyler didnt get kicked out or anything dramatic but he spent the rest of the night giving me the cold shoulder and acting like I betrayed some brotherhood code. Later on he sent me a bunch of texts saying I made him look like a thief and that friends are supposed to have each others backs even if someone makes a mistake. He thinks I should have just nodded along and maybe offered to help pay for it later instead of throwing him under the bus in front of everyone. I honestly dont feel like I did anything wrong because I literally warned him and I am not going to take the heat for his entitlement. My other friends are split on it. Some say I was right to be honest and others think I was being a "snitch" over something small.
TL;DR: Friend opened an expensive bottle of whiskey without asking the host and tried to say we all decided to do it. I told the truth that I warned him not to and now he says I am a bad friend for not having his back.