Heaven, ghosts and material possessions

The current book I'm reading (I always have a book going) features a recently deceased ghost who is belittled by fellow haunts for staying connected with "things of this world" and not letting go of friends, family and, especially, her boyfriend. The ghosts want her to ascend beyond this world and join their world -- a place only accessed by clearing the mind and letting go of everything, also known as "achieving clarity."
Although the novel also features vampires and other supernatural goodness, what struck me most was "things of this world." Some ghosts are not given access to the quasi-limbo world, which leads to Heaven, because they can not let go of human emotions and the people and places associated with them. Instead, they continue to obsess on these emotions and connections and, in time, delve deeper and deeper into madness.
Part of me laughs at this notion, that is, the scared part of me. The part of me that does not want to think about ideas bigger than me and everything. These ideas don't provide answers, they fuel more questions. This part of me thinks of the movie "Ghostbusters" and the famous line, "I ain't afraid of no ghost!"
The other part of me wonders about material possessions. Do material possessions include people or only physical items -- cars, houses, clothing, shoes, jewelry, electronics? Why do you buy a new pair of shoes or the latest smartphone or a new car? The positive feelings gained from buying a new outfit are similar to the feelings gained from popularity or approval from friends and family. It feels good but does nothing to build true self-worth.
As Oscar Wilde put it, "To love oneself is the beginning of a lifelong romance."
Think about your life. What/who is important to you? Most important are probably the people in your life: spouse, children, family and friends. Then comes your current job/career, the place you call home, your hobbies ...
Life is like a video game, you advance and it becomes harder but you are more prepared -- you learn from mistakes and grow or, in a game, you earn bigger and better weapons. You reach different levels: from taking your first steps and saying your first words to graduating from high school to getting married to buying a house to having kids. For video games, you defeat a nefarious turtle monster to advance to Level 8. You are always learning, always changing, always growing to get to the next level. Your sights are always set on something, whether it's a promotion or engagement, that will make your life better. Saving money for a vacation or new car or new house or putting in extra hours at work for a promotion.
However, of all you learned and physically acquired over the years, what do you need when you die -- the ultimate final level? I could get all hallelujah religious and quote the Gospel of St. John: "Love not the world, neither the things that are in the world," but, religious or not, what happens after you die? Maybe there's no Heaven or Hell, maybe we become ghosts and haunt the mortal plane or maybe we go somewhere else, a different dimension or planet. Whatever happens, it's likely, unless you believe in reincarnation, you won't be on Earth, living a life as you did before. It's likely you will be somewhere else. A new adventure.
So, with this is mind, why do people get so caught up with material possessions? What do these items do for you? How can you gain insight spiritually or become a richer person inwardly when you worry about how others are treating you or about buying that silk dress to further compile your fabulous wardrobe?
I understand living your life to the fullest because you aren't sure what comes after death but shouldn't you focus on spiritual and emotional development over hoarding items? Isn't taking a vacation with your spouse and being there, really being there to talk and laugh and live, isn't that better than buying a $300 pair of shoes? I don't want to be on my deathbed left with a closet full of clothes and shoes and no memories of ever living. I don't want to be dying and worry about my regrets and the things I should have said to my loved ones or be filled with anguish over not spending more time with this person or that person. When people are dying, what are their main regrets? Not spending quality time with loved ones or treating their loved ones poorly. They think about what they should have done now they won't have the chance, now their days in this world are over: telling a certain someone how much they love them and how they feel, deep down, the things they were too afraid to say or the things they didn't say because they were busy working or doing this or that, too busy with "things of this world." Why is it so hard for us to acknowledge this and act now while we have the chance? Why do we instead focus on material possessions and follow the same consumer driven path?
People worry about being liked and accepted, buying clothes and items to fill their homes, offices, cars and world because it's easier than thinking about death. Death is the ultimate elephant in the room everyone chooses to ignore. The clothes and the people are here, right now, in your face -- a distraction. So, are you more focused on "things of this world"? Would you be able to let everything go when you die and advance to the next level?