I think that everybody pays according to his/her budget and depending on the sum of money which should be paid.
Sometimes it is better to pay out your hosting plan for a longer period as in this case the monthly price is decreased for you.
The price issue isn't as simple, as it seems to be. Usually, the company's homepage features the best monthly price, but in reality, it can be valid only if paying for a long period of time and on first payment. Thus, you'll have to pay a large sum in order to get this price.
Let see a Total Cost (Monthly Price vs Payment Period) ratio of 10 hosting companies in order to determine whether it is more profitable to pay a large sum of money at once or not.
The price details can be seen on the next picture:
http://www.hostingdiscussion.com/attachment.php?attachmentid=370&stc=1&d=1351006044
As The Table Shows on The Example of JustHost and HostGator, Low Price Doesn't Necessarily Mean Best Price