There's something called Yog's Law.
"Money flows towards the writer."
Yog Sysop created this as a simple meme to help people avoid crooked agents and sleazy vanity publishers. Now, there's nothing wrong with paying money up front for specific services for true self publishing - providing you have it and aren't, you know, selling your inheritance or mortgaging your house to get it. I've bought cover art before. A lot of us pay for editing. It's when a publisher promises you the moon for X dollars.
There's a much smaller scale version of this - and that is reading fees. Just today I was directed towards a literary journal that promised to pay $10-15 for each piece of fiction and $8-12 for poetry or artwork. (They didn't specify what would get the higher end of the range). Except that they charge $4 for each submission. Instead of charging readers, they're charging writers. Nice little racket if you can get it. If you charge readers or rely on advertising, your offering has to actually be appealing. Oh, and their maximum word count is 5,000 - meaning quite a few of their writers will be being paid token rates.
Far more common is the convenience fee or "administrative" fee for electronic submissions, normally $3-4, and charged by some quite reputable academic journals. They claim this isn't a reading fee because they don't charge for postal subs and it "costs about the same."
It's still a reading fee, whether they like it or not.
I don't pay reading fees. (I would consider entering a contest with a large prize that had reasonable entry fees - some wholly legitimate contests charge entry fees to cover the prize amount, but the ratio is always reasonable). I'm certainly not going to pay $4 for a chance of getting $15. That makes the lottery look like a better use of the money.