Hi!
This is an old thread, but if someone is still looking for a work-around...
1. Select a Google Group you want to have appear in Apple Contacts
2. Click to edit the title of the Google Group
3. Select and copy the entire title
4. Exit the title-editing mode
5. Open the first contact of the same Google Group
6. Click to edit
7. Find the Notes Section and paste the title of the Google Group, there.
8. Do the same paste into the Notes Section of every member of the Group
9. Go to Apple Contacts.
10. Under File, select "Create Smart Group"
11. Paste the Google Group title, here, as the title of your new Smart Group
12. Paste again, in the empty blank beside the options Card contains ___________________.
13. Click OK and your new Apple Smart Group should populate to reflect your Google Group.
As long as you consistently update every change in Google Contact notes, your Apple Smart Groups will always stay up-to-date. In the future, you can also compare the number of contacts in a given Google Group and it's parallel Smart Group to be sure you have the same number in both. Google Groups gives you a total number per group. Smart Groups don't, but by Selecting All contacts in a Smart Group, Apple Contacts will also give you a total number.
This is a bit tedious, but it works. I print envelopes from Apple Contacts Smart Groups. I have never learned to use Word Mail Merge, but this works for me.