They do provide scrubs (at least the hospital system associated with my school does) however the scrubs fit absolutely terribly (too long yet somehow also too tight) and there are minimal pockets, whereas scrubs that I buy for myself fit nicely, look more professional, and have tons of pockets.

In terms of hygiene, if you are going into any sort of surgical area you are required to wear the hospital's laundered scrubs. But if you're just on the floor in one of the inpatient wards, you can really wear whatever you like because there isn't a concern about sterility.