There must be something seriously wrong with your network.
I'm running a PC, Laptop, Wii, DS, PSP, Printer, PS3 off of my router. I also have my receiver with FM / AM radio (and XM), Microwave, HDTV, Cable Box, and tons of other electronics. On top of that, there are about 9 wireless networks within range with 50% signal or more.
I have never once lost connectivity with my systems.
In other words, you may want to learn a bit more about wireless connectivity, etc.
Also, it's worth noting that WiFi is generally faster than mots broadband internet connections, so using LAN really doesn't offer any "speed" advantage, and at most, will give you "stability" if your network has serious issues. Mine does not.
Still, excluding a feature that a large portion of your user base would appreciate because you want to make so much money is a little...ridiculous. I understand business is business, but still...sometimes you have to put the consumer first.
Uh... no. There is nothing seriously wrong with my network, other than my choice to use old equipment that satisfies my requirements. Using an 802.11B Lucent RG-1000 WiFi router manufactured in 2000. It's essentially the same router as the original Apple Airport. It even has a built-in 56K MODEM for those without broadband access. In fact, I used it with my telephone line when I didn't have broadband service in my area. It dialed into the MODEM pools at my work for internet access.
Interestingly enough, if I really wanted to, I can still use it in that way and play online with PS3, 360, etc over 56K dial-up. The other players would definitely complain about the lag.
Of course, one of the reasons I haven't bothered to upgrade is as you state. My broadband connection speed is well within the theoretical 11Mbs of 802.11b -- in real-world case, the 802.11B is actually a similar or a bit slower because of the following reasons:
* Variable SNR based on distance
* Interference from other radio transmitters.
I don't know how you can say *any* WiFi connection is not affected by interference on the same radio frequency. That defies logic. Of course, you may have a robust error correction or error recovery algorithm that helps maintain a connection. Before Lucent turned to Agere, and before they stopped maintaining the firmware on my router, it had a very poor ability to maintain connections when my microwave was going off (also from 2000). A firmware upgrade improved it such that the connection degraded, but did not timeout with a "Microwave oven noise fix" listed in the release notes.
Now, fast forward to 2008. My work -- a good sized University with a campus-wide 802.11G network recently had a bout of access point firmware upgrades required due to... guess what? Microwave oven interference. One of our network engineers from the IT department was walking around with a laptop running software that had an O-scope type display showing the signal to noise ratio of his WiFi connection. He did an experiment where he turned on the Microwave oven in the kitchen, and witnessed the SNR degrade on his connection to the APs. Interestingly, the connection stayed this way for a good five minutes after the microwave stopped emitting. Eventually, this was fixed with a firmware upgrade. We determined it was a case where the affected APs may have somehow detected a bad SNR between it and and client interfaces, and adjusted its frequency, channel, or whatever it does to try to correct it, but failed to return to its previous state after the microwave stopped. I really don't know the details, but it was strange. Most of our network equipment is Cisco or Enterasys, so I suspect the wireless kit is pretty well established.
My point is, I've never seen a wireless network as reliable as an ethernet network. Of course, I've also never seen a fully reliable ethernet LAN either. I do miss the days when a 10B2 LAN segment could be brought to its knees when someone popped a terminator off accidentally.
I am just simply saying that an ethernet LAN is the most stable and reliable network option for online gaming. Any wireless connection has the potential for more noise. Whether you notice any ill effects from it, I can't say... but that could just be due to the fact that programmers have to assume an unreliable connection these days when writing network code.