It's a good point, though they did also measure how time-stressed people felt. People who felt time-poor but didn't buy time-saving services had poorer life sat

It's a good point, though they did also measure how time-stressed people felt. People who felt time-poor but didn't buy time-saving services had poorer life satisfaction. If you were time stressed and bought the services, you were protected from some of the negative effects. "In contrast, for respondents who spent money on time-saving purchases (n = 804), the negative effect of time pressure on life satisfaction was relatively weak, B = −0.03, Z = 1.46, P = 0.144, 95% CI (−0.08, 0.01). These results suggest that using money to buy time indeed buffers people from the negative effects of time stress on well-being."