Definitely a useful thing to have, remember as a kid in post soviet Russia we had a kinda similar technology, but it was used not to cool you, but to make warmer, and people used it, for example, if they had a cold or just to warm, there was some substance inside and you could press the button and it got hotter and started to warm you, and in order to cool it down back you needed to boil it, so the substance inside got cold back after that
Definitely a useful thing to have, remember as a kid in post soviet Russia we had a kinda similar technology, but it was used not to cool you, but to make warmer, and people used it, for example, if they had a cold or just to warm, there was some substance inside and you could press the button and it got hotter and started to warm you, and in order to cool it down back you needed to boil it, so the substance inside got cold back after that