Yea honestly if you don’t care about the job, the people, or a future recommendation you can just quit. Otherwise if you want to leave on a positive note 2 weeks/giving a last date is polite. Also depends on the industry- food service is much less formal than an office job, so that may play a factor too. But just know if you give the two weeks they might just have your last day that day to avoid people wasting their last two weeks.