I enjoy having the latest tech in my hands. It's a device I use constantly, throughout the day, every day. In many ways, it's my portal to the world, my connection to my friends and family, my way of recording the things going on around me, it helps me get places, find what I'm looking for, direct my media entertainment, and even play games from time to time. It's what I use to identify music, people, events, and food. It's what I use to make sure the dog treats I'm about to buy really are made in the US. It records my trail runs with interactive, informative data maps afterwards. It also records my drum lessons, lets me write new drum tracks. I also use it from to time as an emergency portal into my work servers. With it, I know my kids are safe, where they're supposed to be, and I can keep tabs on my critical services at home, too. There's so much more, but you get the point.
In short, this is a device that is a key component to many aspects of life, is something I'm using constantly.
I really enjoy having the most capable device with me for all that and I have the cash to make that a reality. There's no need to justify it, really. Some people spend hundreds of dollars a month on cigarettes, or alcohol, or starbucks, or clubbing, new clothes, video games, whatever.
Provided we're not hurting people by it, where we spend our money for things we enjoy isn't something that requires justification.