Retirement fund? Ketchup? Kids? Credit?
Food isn't cheap, but compared to rent it absolutely is. Eating ketchup and rice versus something that will actually sustain you isn't the difference between paying rent and not paying rent. And not paying rent means homelessness, which is rampant in the US exactly because income and living expenses are so detached from one another. For middle class people with savings and security, sure, they can take a few days off work without destabilizing their lives. For a lot of people, though, that's literally not an option.
Praxis in this case for people who do have retirement funds and access to credit that isn't explicitly predatory and aren't struggling to pay the bare minimum to have somewhere to live may be a matter of actually being willing to help make it possible for the people who can't to participate in something like a general strike. If the people who do have financial stability were willing to help prop up the people who don't we might not need a general strike to begin with.
I don't think the solution is for the poorest people in our society to let their lives implode with no assistance while the middle class takes a few vacation days.