Exterminating an entire race, along with any political competitors like Priests, along with any handicapped children, so that you could take over the lands, homes, art, and gold of the former, and have a Germany for 1,000 years, is a lot different than bomber pilots that were trying to bomb cites to force their government to stop the war. Think about it, the smiling camp guards were purposely exterminating huge populations to steal their countries. Bomber pilots were trying to save them, and Europe. BIG difference.
Both are obeying orders and would rather like not be there. My comment originated from the comments that were astonished at seeing people "having fun". Bombers know they are mass-exterminating innocent people who have no decision power. Those employees were not necessarily knowing about the intentional mass extermination. There were a large number of deaths for typhoid fever in those concentration camps. German soldiers - believe it or not - also died for the same cause (certainly they were not cremated in the same ovens). Life was hard for everybody, though much harder for the prisoners!
Taken at a personal level, I don't see the difference. People want to escape, people laugh, people need distractions, people want to live a normal life as much as they can.
Taken at the historical level, things are a bit more complicated but yes, certainly the German government wanted to make an "empire" in Ukraine and Belarus just like the one the British did in India or Africa. They certainly did not aim at exterminating the Slave people. Just at enslaving them or, if you prefer, colonize them, and create a two-layer society, with the Untermenschen in a subordinated position.
(If this reminds you of the US of the same time, that's because it is exactly that. A racist country which fights another racist country in the name of freedom!).
If you subscribe to the British Imperial doctrine that the British were on a mission to civilize Barbaric India and Africa (which, to be true though politically incorrect, is not entirely unfounded) you can claim that Slave peoples were as much civilized than the Germans so there is no ideological basis for the creation of an Empire in Eastern Europe.
Yet, I don't subscribe to the rethoric (that's OT) about WWII. The fairy tale that the Allied were on a mission for Good against Evil. France and Britain declared war on Germany because they wanted to contain German might. Not because they wanted to defend the freedom of Poland. The Soviet Union invaded Poland, Estonia, Latvia, Lithuania, and Finland two weeks after Germany invaded Poland, and there was no battlecry for freedom of those countries. The problem was Germany, not Freedom.
The final outcome was that East Germany, Poland, Estonia, Latvia, Lithuania, Hungary, Checoslovakia, Romania and Bulgaria ended up under the Sovietic Empire, in the hands of foreign-directed dictators. Europe overall was less free after the war than before. Not entirely the fault of Britain and France and the US of course! But it was not a war for "the freedom of Europe" for sure (or if it was, the outcome was certainly a failure).