It's astounding to me how often, when troubleshooting for someone, I find up to 1/4 of the viewing area in the browser consumed by a stack of toolbars. Once I deleted all of them and the person sent me an email the next day thanking me for "making her browser bigger."
This is the quickest way to determine someones level of tech savvyness, it is inversely relational to the number of toolbars they have installed in their browser (developer toolbars excluded of course).
It seems now that almost every piece of Windows software I install wants to install some sort of browser toolbar unless you opt out.
Pherhaps this is one of the reasons Macs are simpler and quicker , there is just less of a culture of bundling crap with every piece of software.
While this shows admirable courtesy, I do feel that extreme prejudice against crapware toolbars is perfectly justified. So, I prefer to take the "shoot first, ask questions later" approach here.
Lots of people apparently liked the Google Toolbar for Firefox (even though it was installed along with other software, hijacked your bookmarks, and generally behaved pretty much like every other malware toolbar out there). More to the point, since it hijacked your bookmarks, if you uninstalled the toolbar all your bookmarks disappeared.