the licencing terms as dictated by the new function added by sharecg can be viewed more as guidelines. your best bet is to specify a more tight licence in a read-me packaged with your file. even better, go get a creative commons licence.
on the practical, real world side of things, your work may or may not be ripped off. secure your licence, so that in the off chance you get ripped off, and somone makes a profit from it, you can be sure to be able to get it all off him.
dont think of it a piracy. think of it as someone else doing the donkey work for you
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