Why they need me to sign up first to download a freeware?

Hi guys,

I was searching for a freeware network analyzer, I know Wireshark is very good, but I came across one named Capsa Free. When I came to their site to download one, but it asked me to sign up a blank first before I can download it at http://www.colasoft.com/download/products/capsa_free.php
Is this secure? And if you were me, will you do it or just give it up?