Should I apply for financial assistance to go to conferences?
Is it worth me applying for financial assistance in these cases? Or is financial assistance restricted to people from developing nations, or to people researching the primary area of the conference, or to people who are submitting papers to the conference?


Every conference has its own specifications for what kind of applicants (if anyone) is given preference for travel grants. Sometimes paper authors are given preferences, sometimes they are de-prioritized. Sometimes participants from underrepresented groups (whether in an academic, racial, geographic, etc. sense) are prioritized and sometimes only US citizens are eligible. Refer to the conference website for details.


  Is the paperwork involved generally long and complex? it is not worth the time to spend a week filling out forms, for a 1% chance of getting to go the a conference -- I could be spending that time on actual research.


No, it's not usually long and complex. Generally it involves some or all of the following: a statement from you on why they should give you a grant, a letter from your advisor indicating that your attendance will be to your benefit and the conferences' benefit, and an estimate of your expenses.


  Are places highly competitive?


Depends on the conference. Conferences that many people want to go to tend to be more competitive.