Flux vs Global Variables (in services)

I am developing flux apps in Angular/NGRX. One intern I am working with said that he used angular services to store data in one of his first applications. At first glance it seemed to me to be incorrect approach, but after a while of consideration I noticed that it isn't much different from the idea of flux store. What do you think, what are the pros and cons of such approach?
Is it much better to use ngrx store, actions, reducers etc. instead of just plain angular services with some getters/setters?
Thanks!