90% of RC planes can be flown without using rudder. Probably 90% of full scale planes can be flown the same way. Some full scale planes actually retract the rudder pedals out of the way after take off.

Many RC scale planes such as Cubs and other low speed aircraft require rudder to make coordinated turns but most do not. While flying my low speed ultralight (full scale), there is no way ailerons alone will make a turn. It must be led with rudder. Same with full scale Cubs. In the early days of flight the sole purpose of ailerons was to keep the wings level. All the WW I pilots that did this got SHOT DOWN!!

If the rudder was required to fly our models then why do so many neglect to use it? Because its not needed most of the time. Should you learn to use it? Of course. Other than trainers and other planes with moderate dihedral it is impossible to make anything but a wide flat turn with the rudder.
Harry has it right I think. Fly with the ailerons and trim with the rudder.