They also haven't had to take the laptop back to the shop in weeks to get the malware cleaned out again and they haven't lost about an hour of every week waiting for windows to reboot after installing updates.
Of the dozens of friends computers I've fixed over the years, 99% of them have only really cared about a web browser, Skype, a basic office suit "where they haven't moved all the stuff I always use", a media player, a torrent client and maybe an email client.
All of them, save Skype, come pre-installed on any mainstream Linux distro. Skype takes about 5 minutes to install through the Mint software manager so I usually show the end user as I install it. The usual response is "...so I don't have to download it then? That's much easier...".
I had to re-install Windows 8 for my brother the other day, it took nearly 2 days by the time I'd installed drivers and Windows had finished installing updates and patches. Directly after install I had to find drivers for WiFi, the onboard video card and bluetooth, none of them worked (video was stuck at 1024x768 or similar). The manufacturer website couldn't tell me exactly what hardware was in the box so I had to Google the Windows equivalent of lspci, I didn't fancy installing some third party tool from a random website I'd never heard of so instead I booted off a Linux live disk to find out.
The same process on Linux (if I install a 3 year old LTS release from scratch and then install all available updates) takes about 2-3hrs depending on the speed of the computer and/or internet connection. Most of the time hardware works out of the box (it certainly did on the above mentioned box), if drivers or tweaking is required to get stuff working, the time spent is certainly less than the AGE that Windows takes to update.