Like I said in another comment, I live in a university town that has tons of non-employed students. Who drink shakes.

Customer service positions are a pain to fill. At any price.

Many students are on foreign visas. Others devote their time and effort to internships. “Working at shake shop” doesn’t look good on resumes.

Life isn’t just about wages, and low prestige jobs are under filled just as high prestige jobs are over filled.