Some do, but they probably get their results from different whois servers. However, they only check whois information of one domain at a time. When you are looking for BULK checks, the whois servers see multiple requests coming in and will block an IP. I would recommend either coding or finding a program that will use proxies and check multiple whois servers.
I personally use sType for finding typo domains, and Domain Research Tool for everything else. I can generate a list of domains I am interested in, load in my list of proxy servers (200+ or however many you have) and let it do the work.
If you are interested in getting in the game then these programs are worth the small investment to purchase.