Your manager should have dealt with this.

at our store weekends sucked but specifically sundays we’re a nightmare. lots of call outs, lots of customers, poor close leading to a poor open, and the dominos keep falling

I have had management in the past who, when it has been stated that a certain day or time won't work because of life, have said "that is too bad" and scheduled that way anyway. I have had it happen to me, and witnessed it happening to others. Please be certain that isn't what is going on before you apportion blame.

For a recent example, a co-worker had school at a certain time when we had no one else "willing" to work that shift. I work in a kiosk, we had at the most seven people at at time, and that was at that time WAY too many people, many of us were not getting enough hours. But at the time of this example we had fewer than that. In our case, we didn't actually need that employee to be there at that specific time, but had to schedule her anyway, so it was fine. I was told she'd be late every that particular day of the week she was scheduled due to school, I said fine because she wasn't necessary and school is important, and off we went. A worse manager would have made that a massive headache, a busier hour would have also made it painful. In our case it wasn't a big deal any way around.

In your case, this really feels more of a systemic issue at the managerial level. Your manager should be addressing this, and rearranging schedules that are not working well. It may be that there is literally not much they can do, if they pull those people you might not have other people to fill those spots, leaving you still short. You might have people coming in as they can, leaving you with holes have the size they would be if those people are gone, and your manager has decided that is the better option. For the manager. If that is the case here, your manager is deciding what they can deal with best, not what is best for the store.

The very best thing you can do, because there is nothing you can do to fix it, is let it go as a problem. It is not your problem, it is not something you can fix. Let go any responsibility you feel for it. Remember the serenity prayer. Change the things you can, release those you cant. Be wise and identify the difference. This is one you can't fix for MANAGEMENT, but you ABSOLUTEY can for yourself. Don't take on extra responsibilities you don't want to deal with. Don't stay longer than you are comfortable with. Don't cover for coworkers unless you want the extra hours and money that comes with it. Take care of yourself first, job second, and even then only if you don't have family that needs to come before your job. If you collapse because of work, the corporation is not going to come to your aid. Fix the mask on yourself first, before turning to help others. And let go of any guilt feelings for doing so, they aren't supporting you in your time of need. Feed your own needs first.

Good luck to you. Remember, there are a billion jobs out there hiring right now. If you truly can't stand this place any longer, you have options. Go forth and prosper, whatever you choose!

We have baristas at my store who have been with the company over 2 years and just come in whenever they feel like it basically and no one says shit. They will just not show up at all for their shifts or show up super late. And the teenagers who are new do this kind of crap all the time too. It doesn’t help that our new manager (who is an outside hire) is also late to every single shift she is scheduled 😅 No accountability at all.