For Muay Thai I fully agree. The gym I trained was very strict about respect issues, and the fights (semi-pro and amateur) were the same as well. I remember many times we changed in the same locker room with my opponent both before and after the game and the respect towards each other was quite high.

I joined some K1 national (amateur) tournaments as well, but that was totally different. Full of jerks and low class. I got mad to someone in the fight who was 10 years younger than me, told him to stop shit talking as it is against the traditons reminding I am a Nak Muay, not a kickboxer. He kept insisting and I used elbows, that caused me an immediate disqualification and him to have enough damage to withdraw from tournament.

Taekwondo gym I cross trained was also close to Muay Thai in sense of respect and I had great friendships, learned a lot from them.

MMA is something that I never dared, but I always thought it as a savage arena. This vid shows probably I am wrong.