Traffic thats not needed

Quick question. I've noticed that when a local game is being played, say Rome Total War, traffic is still being sent over GIT. I have know idea how much is being sent but in the forwarding log it is showing information being sent.
It does seem to be having an effect on the bandwidth overall
Here is a small cut from the log:
This was noticed after 7 people were playing CS online while 4 were playing a local game of Rome Total war (not between LANs). Pings were at 150-200 for the CS players until I turned off GIT. I waited a while then turned GIT back on, where the increase in ping returned.
We can normally support 8 CS players online fine without pings going up.
Is GIT sending information to do with the Rome game even when there are no players at the other LAN playing ?
GIT ports used:
18321: total war
26220 : Rome
34987 : Rise of Nations
5555 : Panzers
6112 : WC3
No other ports were open while I was looking into it and I was getting the same with just these ports listed.
Cheers for your time.
It does seem to be having an effect on the bandwidth overall
Here is a small cut from the log:
[Sat Feb 05 12:32:17 2005] network: hw:00:e0:4c:c1:b0:ef EthernetII ARP request to:00:00:00:00:00:00 from:00:e0:4c:c1:b0:ef(192.168.1.109) for:192.168.1.98 'ok'
[Sat Feb 05 12:32:17 2005] network: hw:00:e0:4c:c1:b0:ef EthernetII ARP request to:00:00:00:00:00:00 from:00:e0:4c:c1:b0:ef(192.168.1.109) for:192.168.1.97 'ok'
[Sat Feb 05 12:32:17 2005] network: hw:00:e0:4c:c1:b0:ef EthernetII ARP request to:00:00:00:00:00:00 from:00:e0:4c:c1:b0:ef(192.168.1.109) for:192.168.1.97 'ok'
[Sat Feb 05 12:32:17 2005] network: hw:00:e0:4c:c2:cd:be EthernetII IPv4 UDP to:255.255.255.255:26220 from:192.168.1.91:26220 'ok'
[Sat Feb 05 12:32:17 2005] network: hw:00:e0:4c:c2:cd:be EthernetII IPv4 UDP to:255.255.255.255:26220 from:192.168.1.91:26220 'ok'
[Sat Feb 05 12:32:19 2005] network: hw:00:e0:4c:c1:b1:20 EthernetII IPv4 UDP to:255.255.255.255:26220 from:192.168.1.90:26220 'ok'
[Sat Feb 05 12:32:19 2005] network: hw:00:e0:4c:c1:b1:20 EthernetII IPv4 UDP to:255.255.255.255:26220 from:192.168.1.90:26220 'ok'
[Sat Feb 05 12:32:21 2005] network: hw:00:e0:4c:c2:cd:be EthernetII IPv4 UDP to:255.255.255.255:26220 from:192.168.1.91:26220 'ok'
[Sat Feb 05 12:32:21 2005] network: hw:00:e0:4c:c2:cd:be EthernetII IPv4 UDP to:255.255.255.255:26220 from:192.168.1.91:26220 'ok'
[Sat Feb 05 12:32:23 2005] network: hw:00:e0:4c:c1:b1:20 EthernetII IPv4 UDP to:255.255.255.255:26220 from:192.168.1.90:26220 'ok'
[Sat Feb 05 12:32:23 2005] network: hw:00:e0:4c:c1:b1:20 EthernetII IPv4 UDP to:255.255.255.255:26220 from:192.168.1.90:26220 'ok'
This was noticed after 7 people were playing CS online while 4 were playing a local game of Rome Total war (not between LANs). Pings were at 150-200 for the CS players until I turned off GIT. I waited a while then turned GIT back on, where the increase in ping returned.
We can normally support 8 CS players online fine without pings going up.
Is GIT sending information to do with the Rome game even when there are no players at the other LAN playing ?
GIT ports used:
18321: total war
26220 : Rome
34987 : Rise of Nations
5555 : Panzers
6112 : WC3
No other ports were open while I was looking into it and I was getting the same with just these ports listed.
Cheers for your time.