Quick announcement: Do not use UPS for international postcards.
U.S. postage rates went up not too long ago, so an oversized postcard needs $1.05 to go overseas.
I thought I'd save myself a bus trip and walk down to the local UPS outlet for stamps, much closer than any of the three post offices in my area. They carry first class Forever stamps, but they don't have them for international rate. However, the clerk offered to run them through their postage processor and I didn't know what the difference was.
The difference is, UPS marks this service up 86¢! What should have been $13.65 for 13 postcards came out eleven dollars more! I'm embarrassed by my poor judgment, but I went through with the transaction to teach myself a lesson. My wife may be upset with me for this needless expenditure, but I'll deserve her resentment, and hopefully this negative association will keep me away from UPS in the future.
I hope you'll learn from my lesson: you can buy Forever stamps at UPS, but for any other mail they are a terrible idea.