You are only partially right Sakorr. Some magick users work through other entities, spirits or demons. Some don't. Some entities require a sacrifice for their aid. Most do not if asked properly.
You do not need any outside help to work magick. It is not an easy path to magick. Summoning is difficult, and it's often easier to do something yourself than it is to ask for help.
You'll need to learn your basics either way. You won't be able to summon anything with any degree of success or control if you do not. Summoning isn't a shortcut, it's just one method of magickal working.