I've spent a good amount if time in gaming LAN centers. I've worked, been sponsored or done tech support for 5. Proper licensing for a lot of games in a LAN center is prohibitively expensive. Most games you have to get special LAN center licenses you have to buy every year. WoW is an exception to this as they make the money off subscribers not game sales, so a LAN isn't a threat to them. People coming in to surf the internet were around 5% of users at any one I've seen.
Now gamers want nice computers, big screens, good headphones, mice, and keyboards. They will then proceed to run over those headphones with their chairs, slam the mice and headphones when they die and get mad, and spill crap all over the keyboard.
A big LAN center usually attracts drug users and I've seen more fights over counter strike than you'd believe. I'm pretty sure the only ones that make money do so by lots of tournaments and sponsorships.
I've thought a lot about this too. We are remodeling soon and I'd like put a small gaming area in. The best idea I've come up with is run the shop 9-6 and the LAN center 6-2am and weekends. A) to keep my business clients from being turned off by riff raff, B) so I don't have 50 computers and a couple servers all running at peak hours, C) to let customers drop off/pick up computers a lot more of the time, D) so were not fighting each other for bandwidth.. paying an employee plus software, hardware, and electricity would be hard to break even, but could be offset by the extra business from being open for drop offs an extra 60-70 hours and increased exposure.
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