HDD are still very popular with people who enjoy saving money, but want to have Terabytes worth of free space for storing files since for 100 dollars you can buy a HDD which can hold 2TB/2000GB of files which mean you can download a lot of your favourite videos, games, music, software, and more, and still have a lot of space left over for more files in the future.
The speed of a SSD vs HDD are also not worth the high price tag of hundreds of dollars in reality for most users since saving a few seconds, but paying hundreds of more dollars for the same amount of space as a similar sized hard drive is not worth it for the common users. They benefit more with speed and usability by buying a computer with a faster CPU, more RAM, a better video card, and a bigger monitor.
If the users operating system is a light weight operating system like Linux, or Windows XP the speed difference will be even less noticeable or worth the high cost of SSD to the average user.
SSD are currently mostly used in Tablets, smart phones and hand held game consoles which only need a few GB of space for the operating system, and a few files and save files for games and apps which only use a few MB of space.