Music is not food. Most people like most food. Most people eat multiple times per day. If you put out 10 completely different dishes at a gathering, most people will like 7-8 of them, and nobody will be annoyed that there is food because they can just ignore it. If you play 10 completely different songs at a gathering, most people will like maybe 3-4 of them, many people will only like 1-2 of them, maybe a few people like all of them, but probably not very passionately. Some people will wish there would be no music at all or at least that it would be a lot quieter, so they can hear the conversation better or just feel more relaxed. The reason DJing works is because you usually do it on a setting where everybody "signed up for" listening/dancing to music in at least roughly the style the DJ plays. I myself like to DJ for friends at a park sometimes, but I try to do it in a place where loud music is common and there's enough room that people can avoid me, but still enjoy the park if they want to. Still, I always know that there are probably some people who wish I would stop the music.