Really? Maybe it is beacuse you dont know how work this exchange?
To trade there you have to own some coins to cover costs of transaction.. In other words, thats why is easy to get in to this exchanges - everyone who want make any transaction must own minimum amount of their coin.. It is the way how their business work.. nothing special, and for sure it is not some kind of fraud. You just have to understand their politic..

Edit: My comment was only about Wave platform. On Tidex you can trade only with fees - more comfortable for you - for sure!