Having other areas of your field with better pay/conditions/benefits can put more pressure on even non union places. Since there will be better contions elsewhere, there will be an expectation of a level of compensation/more people looking at those union places, requiring even the non union locations to at least increase something to compete for talent.
Complete assumption as to why the parents did, but COVID showed a lot of cases where people defied health orders, as they couldn’t financially survive with losing a couple days of work as they we’re already so tight. And that was before we hit post-COVID inflation! Not to defend their actions, but I can see how this came to be.
It's Been A Bad Year For The Video Game Industry, But A Good One For Unions (aftermath.site)
Secondary cases of E. coli grow in aftermath of Calgary outbreak: Alberta Health Services (www.cbc.ca)