Phrased differently, why do you think it would be a sin?
No, I do not think there is any “sin” aspect to what you describe.
If she’s being lazy, that’s not a good thing. If she spends all her hours at the mall buying 500 pairs of shoes, ditto. I think auditioning for “Housewives of Orange County” might be an example of someone whose time on earth is not being particularly well-spent, but based on what you are describing, the actions seem to fall into the category of being neutral, i.e., not really noteworthy one way or the other.