Personally I have been through this, I have created so many projects for free with the promise of continued and future paid work.  I can go online and find things I have done throughout the past, whether it be digital or other.  You go in thinking, finally, this could be my break, but nope, you are just used for the free work.  So many people have done this to me.  What I need to do is make an agreement for the use of my things, and no longer do ANYTHING for free, whether it gets me out there or not.  Because my talents are still not known.
        Usage tights, much needed.  This allows us to get credit for the work that we have done, with possible additional compensation.  That work is ours, and can only be used according to the agreement.
       Logo mill... Contests from companies get designers to create logos for free.  To enhance ones chanced of winning, some 'designers' put out a bunch of 'crap' logos and also a lot of plagiarizing happens with these contests.  People do not put their hearts into their work as they should if they truly want to be a graphic designer. 
These 'contests' are not cool.