Do you consider buying game assets (which you use as a tool to complete a project) to be the storing up of treasures? You might want to read some commentaries on the passage of scripture convicting you.
Vincent word studies says : "Lay not up treasures (μὴ θησαυρίξετε) Lit., treasure not treasures. So Wyc., Do not treasure to you treasures. ..."
JFB:"Lay not up for ourselves treasures upon earth--hoard not. "
Barnes: "Lay not up for yourselves treasures upon earth - Treasures, or wealth, among the ancients, consisted in clothes or changes of raiment, as well as in gold, silver, gems, wine, lands, and oil. It meant an abundance of “anything” that was held to be conducive to the ornament or comfort of life. As the Orientals delighted much in display, in splendid equipage, and costly garments, their treasures, in fact, consisted much in beautiful and richly-ornamented articles of apparel. See Gen_45:22, where Joseph gave to his brethren “changes of raiment;” Jos_7:21, where Achan coveted and secreted “a goodly Babylonian garment.” Compare also Jdg_14:12. This fact will account for the use of the word “moth.” When we speak of “wealth,” we think at once of gold, and silver, and lands, and houses. When a Hebrew or an Orientalist spoke of wealth, he thought first of what would make a “display;” and included, as an essential part, splendid articles of dress. The “moth” is a small insect that finds its way to clothes and garments, and destroys them. The “moth” would destroy their apparel, the “rust” their silver and gold; thus all their treasure would waste away. The word rendered “rust” signifies anything which “eats into,” and hence, anything which would consume one’s property, and may have a wider signification than mere rust."
Are you hoarding an abundance of something? Do you see a difference between buying 30 pairs of designer shoes and buying 1 pair of sneakers, 1 pair of work boots, and 1 pair of business shoes? Or are both examples of "hoarding" an abundance of treasure? Is there a time to buy assets, or can you never buy anything? Ecc 3:1 To every [thing there is] a season, and a time to every purpose under the heaven:
Ecc 3:5 A time to cast away stones, and a time to gather stones together; a time to embrace, and a time to refrain from embracing;
Ecc 3:6 A time to get, and a time to lose; a time to keep, and a time to cast away;
Joh 12:5 Why was not this ointment sold for three hundred pence, and given to the poor?
Joh 12:6 This he said, not that he cared for the poor; but because he was a thief, and had the bag, and bare what was put therein.
Joh 12:7 Then said Jesus, Let her alone: against the day of my burying hath she kept this.
Joh 12:8 For the poor always ye have with you; but me ye have not always.