Nope! A gun is a great investment, a nice firearm will hold its value better then the stock market has over the last decade, sometimes the right purchase can increase over time.
Plus it can save your life.
I bought a cheap s&w SW40ve for about $229.00 effective after rebates, etc. Very nice gun, very nice price
*EDIT* a gun like that will probably not hold its value as well as something with better manufacturing, but on gunbroker I can already sell it for more then I bought it for and used guns of inferior older models go for more too