Why do some Canadian Class E airspaces have no ATC frequency on VFR maps?
In class E airspace, ATC service is provided to IFR flights, but not to VFR flights. The "NO CONTACT" note most likely refers to VFR flights, since you are looking at a chart designed for VFR flight planning. The airspace is class E, and not G, because whoever designed it wanted IFR flights to be controlled within in.

See this related answer for a brief description of the different airspace classes.