Cape Cod Massachusetts USA
A key issue is the motivation of the contest administrators.
If you are expected to pay a fee for your work to be included in a publication, it's highly likely that the book will be available exclusively to its participants. No one else purchases the publications. That would be quite self-serving on the parts of the administrators, wouldn't it?
Conversely, a publication such as ours here at Passions is compiled for the benefit of our members. We have a very intricately fair means of choosing the poetry for inclusion in our anthologies. Our administration makes no profit on its publication, but rather makes the books available to our members at wholesale rates and encourages them to resell the books for their own profit...
It's a no-brainer, methinks...