What's with the Captcha Widgets that won't Captcha?

Are they designed to work in IE alone? I’m hitting more and more Web forms with a Captcha script that can never be satisfied. The characters may be easy enough to read. I check what I typed to verify it is what I see. I look to verify that the caps lock isn’t on. And still, way too many scripts always answer back that the input did not match, please try again. I’m down to 2 tries now. If a webmaster’s Captcha doesn’t let me contact them, I’m off to find somebody easier to deal with. How about you? Are you seeing this in Chrome, Firefox, Safari, etc? What’s your response to troublesome or unreadable Captcha Widgets?

Why not just design the form handler CGI script in a bulletproof fashion and simply delete emails submitted by spam bots?