Did the coins always dissappear or is this new?

There has been a change to the way holiday tokens and items work. If an item's tooltip says it requires that holiday, that means it will remain as long as the holiday is up and will automatically disappear from your inventory when the holiday ends. That tokens are included in this is intended.

Remember that your in-game calendar will tell you the precise time when the holidays begin and end in server time, so if you're uncertain if you're going to have enough time to complete things in the future, make sure to check your calendar.

We have no plans to restore the coins. The coins going away was something that happened last year as well, and it was not a bug then, either.

If you're looking to get the meta achievement, it does not require you to spend every day doing the dailies, or even half the days of the event. Yes, it will require some dedication, but if you do not have the time to spend to get all the achievements in one year, that's perfectly understandable; the holiday will be there next year, and you can focus on different goals.

Don't get me wrong; I am sorry you were unable to complete what you were after this year due to the change in functionality and waiting until the end. In the future, it may be advisable when you have the opportunity to take care of things as they come rather than waiting til the last minute.

Since last year's Brewfest, the tokens were intended to expire before the following year's Brewfest came around again. If people found ways around the old expiration, that doesn't make it less of a bug if they remained. Only the tickets from 2007 had no duration. It's partially because of that ability to work around the timers that this new functionality was implemented.

I do apologize that you weren't better informed about this particular change. Moving forward, I'll be sure to remind the playerbase during token-based holidays that they will expire, and I'll speak to the web team as well to work that information into the official holiday pages so this does not happen again.