You're not making much sense. You can subscribe to a group, which lets you know when there's activity in a group, but according to you that's a pain, however getting notifications that do exactly the same somehow isn't? While the latter would probably be far worse? Imagine that each of your 30 groups gets a single message posted a day, that would mean 30 notifications as frankly one notification for all groups is completely redundant. In fact it's redundant to the entire concept of notifications, which are meant for you specifically: you received a VM, you received a PM, you received reputation, you received a friend request. However it's not you specifically who received a message when someone posted in a group, that's for the group. You don't get either notifications when people make threads and posts around the forum. Hence the existence of the subscription option so that you can somehow be informed by certain things.
Getting notifications for group messages would just be inconvenient, redundant and cause an unnecessary strain on the forum when everyone starts to get notifications of the groups they're in.
