It was never disrespectful. I just saw this several times on ragnarok mode, even already at the end of wave 1 and 2. I fully understand why doing so, as everyone try to come as far as possible in this evil mode, but I'm not sure whether re-joining or requesting to re-join might be considered as a kind of glitching or system abusing.
"Swadians are cowards - they just hide and shoot" - King Ragnar