Will my son be able to find another job after this?

I had no idea my son was planning on quitting his job. He's 18 and works at Starbucks. He worked his full work week and then told his boss fuck you and quit at the end of the day. He didn't leave a two weeks or anything. I know Starbucks isn't the best place to work but I'm just concerned he won't be able to get another job after. My ex thinks I'm being overdramatic and said he's seen people full on rage quit and have a job within a week and as long as he doesn't make a habit out of quitting that way be will be fine. I just feel there's a way to do things and that's not it.