<sarcasm>But it's perfect!</sarcasm>
"Why are you so uncomfortable with running these random scripts from the internet that load with every page you could ever want to visit?", you ask, "They're harmless."
Well, unknown reader of this blog post, the fact is that they are not harmless. Many scripts are externally sourced, often proprietary or obfuscated code that can do a number of things to your privacy, your security, and your personal computer. Popular analytics services for instance; these scripts grab personal infortmation such as your current location, your device information, information stored in browser cookies, and then conveniently package them up (often with a unique user ID to identify you and your browser) to track you and your browsing habits.