That's colloquially referred to as retail therapy. I don't think occasionally indulging in it is bad as long as you're cognizant of its purpose as a coping mechanism and understand the relief/pleasure it provides probably isn't going to be long-lasting.

In my family, all impulse purchases had to be "justified" with whatever flimsy reasoning was necessary. I don't think that's any better and if it's not coming at the expense of things you actually need, it's good to be able to decide you want something just because you do. Otherwise you can start going down the path of, "Do I really need cheese on this burger? Do I really need variety in my food? Do I really need to be eating three times a day?"

Life should be lived, just don't lose sight of the big picture of course. Also, I'm sure other people around you approve of your buying deodorant :)