I dunno, calling someone a scab, possibly changing your attitude towards someone who you were previously sociable with and employees suddenly stopping swapping shifts/hols/cover as a pp mentioned because they didn't strike is pretty questionable conduct and bordering on bullying. I don't think it elevates those doing it to the higher moral status they mistakingly believe they hold by striking anyway.
i dunno, joining a union for the protections, voting to strike then not striking and your colleagues who did strike and lost out financially finding out? And them not being all sweetness and light as it was before? Piffle
If you join a union you read the terms and conditions, you look up what the union does, what it believes and what it expects of you. I notice OP is clear that there are benefits to being in a union, so presumably she read up on the bits it would do for her and less on what her contribution should be.
Scab or not - if someone crosses a picket line, and they are a union member, they can't expect everyone to love them the same. It is a big move and that is why union membership needs to be considered. On the other hand scabs get all the benefits won by collective action, and i don't wonder that people who have suffered financially are sour about it.
So again, i am now going to assume that OP won't do this again. Or will leave the union. That is up to her.
I hope that anyone in precarious, dangerous, underpaid and overworked employment considers joining a union (there are benefits outside industrial action and collective bargaining, including employment legal cover and insurance). But it isn't a free ride. That isn't what the union movement is about.
(FWIW - when my union are picketing supermarkets or whatever, that i would usually wand to use, i go elsewhere. Because that is what being in a union is about - supporting each other. The workers)