I just got my new Nexus 7 and found out that most big Android games download their data over WiFi. This is problematic for me as I don't have a good WiFi connection and most downloads freeze halfway. Can I download the extra data on my wired connection on my computer?
It depends on game. Some games allow you to download the data off phone and extract it to your SD card at the said location of the game instruction. I remember doing so for few games myself.
If the game instruction doesn't have anything like that then you've to manually find out what file it downloads from where and put it in relevant place in SD card.
If you root your tablet, there are reverse tethering apps that will allow you to use your PC's net connection via USB. One of the apps in the Play store is free, and another offers a free trial, so you may give them a try. It appears this working is hit or miss, but since this is a Nexus device you may be in luck (being vanilla Android, not some carrier or manufacturer's possibly locked down version).