Bags- I know it stinks that your sander failed jut after warranty ran out but the terms of the agreement have to end sometime. If it were a ten yr. warranty and it failed after 121 months we'd still be miffed. In any case , I think there is no excuse for a premium tool's bearing to fail in three years. Even if it were to be used everyday in a professional setting.
The sad reality is most replacements/repairs don't make economic sense for tools and appliances. This isn't limited to Festool. Also, have you actually tried to collect on a ridgid warranty after three years? It sounds good, but reality is much different. Now, some store managers will goodwill you something on ocassion but it's not policy and the terms of the warranty have you send in the tool to ridgid corporate. Kobalt and Snap On aren't going to give you an new drill or sander for yours when its warranty expires either.
The other sad reality is Festool has no real incentive to alter things because we keep buying their tools. If you really want to make a statement , return that new sander you bought with an explanation why and sell the rest of the FT gear. Buy something else. Otherwise it's like any other capital expense for machinery. Some are just better values than others but no brand has winners in every catagory.
Naildrivingman - Festool raises their prices every year too. I think there's a bit more too it than that.
Aloysius - were you aware that FESTO and FESTOOL are totally separate companies today ? They have nothing to do with one another regarding operations management or ownership. Festo no longer produces tools that are used for woodworking.
Your math is incorrect. $167 is not 25% of a new DTS. It's actually 64% like Svar pointed out and that doesn't include the postage cost which you will incur both ways . When you really look at it , bags' repair will cost MORE THAN a new sander. You see, the new $260 sander includes free shipping and a new systainer2 which costs $76. And he wouldn't have the benefit :

of a three year warranty. I think it'll be hard to find anyone to agree with you that that is not an expensive repair.