Lots of fake people subscribe to newsletters and lots of fake customers register. Is there any way to check such emails in the admin panel and remove such customers in bulk from panel iteself.
Why not just use Captcha for subscribers and users? That usually does a pretty good job. It won't fix the "spam shops" that have humans actually doing the work. Nothing will.
You can search users and use a segment of the email address for a list of matching users. Not sure about subscribers. I don't use cs-cart subscriptions....
Also, using Mailchimp (built-in or our enhanced EZ Mailchimp addon) for subscriptions/newsletters does a pretty good job of filtering out the lists with much better heuristics that you can ever get here. But you do need to be cautious about your site being viewed as a spam site if you're sending mail to spammers who in turn use your From address in their spam.
Please take a look at this add-on:
A lot of cs-cart admins are using it to eliminate the fake emails, spammers.
Maybe helps.