One thing I remember glowsticks being used was at Keystone Strike 2. We used them to set up a defensive perimeter around the deuce in an open field. My guess was that they were going to be used to sihlouette any targets approaching the deuce so we could hit them (they were spread out just at about the edge of AEG range), but inevitably because of the limited brightness and the way they were spread out, all they really did was point out people sitting next to them (which happened at least once), and denote the area where the deuce was (which was handy, as I have piss poor natural night vision and no night vision equipment to speak of excluding a flashlight).
There were a few people with gen2+ NVG out there, they managed to find us quite effectively, and when the chemicals in the glowsticks waned (IIRC these were milspec stuff) they were pretty much totally useless and defenders just waltzed in and peppered the area with grenades and sniped at us.
Not very effective, however the 3000~ (IIRC) lumens 'god light' we had worked wonders