Even if you receive the biggest stipend out of all graduate programs in the entire country in computer science or whatever stem subtype you'd like to name, it won't be much higher than 35k/yr. Grad students in top programs in Boston and the bay area are living on the razor edge of affording a roof and food. It doesn't get much easier in the midwest, either. Your rents are cheaper but your stipend is comparatively lower, and opportunities are more difficult to find compared to networking on the coasts which are hubs of tech and biotech.
The current stipend is just not enough to pay for rent in Santa Cruz. In recent years the city has become a bedroom community for bay area commuters and appropriate housing supply hasn't been built to match the influx of people. There are grad students at ucsc where it is cheaper for them to fly across the world back to their home country for the summer than to live in Santa Cruz for those three months.
There are also graduate students who entered their program under a different union contract, with a different rental market landscape, and now find themselves with the prospect of being unable to pay for a wildly higher rent than they expected from data from 2016, something that they couldn't forsee when the signed their fellowship contract 4 years ago, so yes, some of these students are being baited and screwed.
On top of this, UCSC graduate students attempted to fix this at the negotiation table, but the agreement between all UC campuses and the greater graduate union did not take into account the rising cost of living in Santa Cruz when it was made; 83% of UCSC graduate students opposed this agreement at the time and their concerns were not heard by their union or the University of California.
For many students, the choices are to starve, attempt to derail their life by dropping out of grad school and reset it in another field somewhere far away from California with their lack of disposable income to even fund a move like this, or to strike and attempt to improve the situation. I can't blame them at all.