Actually, Ikea did do this... And it wasn't even 12.00 for the initial mug.
The cafeteria in our local hospital does the same thing. Buy the travel mug once and you can re-fill as long as you want. My 90 year old Mom has been in and out of the hospital now for 6 months (multiple myeloma, heart attack, kidney stones....gosh knows what else is ahead).
The cafeteria food is actually very good. The heart attack visit I was in the ER with her late at night waiting for a bed on the cardiac floor for transfer. The guard reminded me they serve a complete dinner at 1 am for overnight staff. I HAD walked out with my hospital mug in hand as I was following the paramedics. I had my soda along with my cream of crab soup. Yummo!