Well it probaby wouldn't be the best idea based on the sized of pixles most of the games are. Look at this X real quick. Mentally enlarge it. See how choppy it is. That is probably one reason why.
The developers don't make their games to be encompassed on a full screen.
Due to the magic of vector imaging, it's not because of resolution. Typically what you see is the 'stage', and all the objects originate off the stage before being put onto the stage.
You can zoom in on a lot of games, but you'll start to see things not on the stage along the edges.
If you want fullscreen, there's an (kind of) easy way to do it on your own.
Go to the game you want in fullscreen. (I'll do K.O.L.M. 2.) Right click on the page, (not the game itself) and choose "view source." Then type ctrl+F. type into the little box that appears "swf." It should go to something like this " /files/games/kolm-2-11743.swf" Copy that. Then go to a new tab and type in armorgames.com. Next, add "/files/games/kolm-2-11743.swf" to the end. Click enter or go. It will be fullscreen. If you want even more fullscreen, press F11.
Why would it be a bad idea if there was a full-screen mode? If the quality is bad, you won't use full screen it. But when the quality is good, you will use full screen.
What's the problem If there come a full-screen option?
If you want fullscreen, there's an (kind of) easy way to do it on your own.
Out of curiousity, did you just copy the method i posted here?
Some game developers do allow full screen, but the ones that don't have their reasons for not doing so. The reason usually is that the game's screen is usually a set size, and when it goes full screen it is forced to be another size. Let's say the game's screen is 5 inches wide and 7 inches tall, if you go full screen than the game's screen may be forced to be 9 inches wide by 14 inches tall, which would force the game to have to stretch everything out of proportion.