Wanna know something cool and/or creepy? A lot of the "canned" laugh tracks used in TV (for shows that pretend to be filmed in front of a studio audience, but actually aren't) are from a small handful of sound libraries that get mixed together. Many of the laughter tracks come from live audiences at I Love Lucy tapings.

If you consider that I Love Lucy was filmed ~70 years ago, and that most of the audience members were likely 20+ years old at the time (the studios were in LA, and the audiences were largely comprised of tourists), then there is a statistically high likelihood that any individual audience member you hear laughing on certain modern TV shows may have been dead for decades.