1) Firstly you can't assume that you only need one eye toy for 4 players unless you can provide me with source.
2) It hasn't been decided on how many players kinnect can support but so far its 2 active players and can scana up to six players. http://www.eurogamer.net/articles/kinect-supports-two-active-players
Reports form microsoft said that it would allow for 4 people . I guess for tat we have to wait till the release date.
http://www.xbox-scene.com/xbox1data/sep/EkZZEVEkpVHFLSoLnK.php
3) my point still remain is that if you want to play a two player boxing you would still have to spend $150 per person because you need two set of controller move games we have seen like archery , gladiator , boxing they all need at least two controllers per person which is ridiculous in my opinion.
