I totally agree with you. They are scammers.

I opened a case with their support for a trade ossue where i lost half of my ENG:
Below was my text:

I transferred 3174 ENG to my Mercatox account and exchanged them to BTC. Then I exchanged back those BTC to ENG. But after the last exchange , I only have 1863 ENG left... can you explain why? are your fees that high?

i opened a case with the support. i didn't get a confirmation that i opened a case.
Also it took them two days to reply, and here is the reply i got:

HI we have trade fees that are 0.025% of trades - rest it is yours price and trades.

And they closed the ticket!!!

Stay away from this exchange!