>For example, is everyone going to disown their friends and family, all for some nebulous concept of society
This isn't "some nebulous concept of society," this is the community that you have chosen to be a part of and are in control of. You say that you wouldn't abandon a family member, but what they are doing is akin to standing up and with a clear mind stating "I don't consider you family and want nothing to do with you." That is what "rejecting society" entails. You would not still blindly support that person.
>mean, you are straight up saying that you don't think these people should be able to have access to food.
These people chose not to have access to food. They are not "disadvantaged," they are facing the consequences they knew they would face for their actions. There's no need to immediately starve them, but they know they can't stay in the community if they won't be a member of it.
>Even if something like 10% of the population is willing to help out people who don't agree with your concept of society, that is more than enough to make sure that these people are still able to survive
It is not "my concept of society," it is something the society together builds. Yes, some people will disagree. They can build their own society and we can coexist.
Most of your arguments have put "me" as the ruler of this society and justify actions as them rebelling against me. This is not how the power structure goes. People may be willing to help those rebelling against "me," but they are less willing to aid someone rebelling against something they themselves chose to enact. Similarly, the punishment for someone harboring such an individual isn't my decision, it's something the community decides based on the circumstances.