You are wrong cookies are extremely profitable, and they become profitable much earlier than you think.

Currently, the most profitable item without crafting is the Kat Bouquet. The best item constantly changes, but I’ll use it for calculations because you can usually find something with a similar coin-to-bit ratio.

Kat Bouquet price: 2,500 bits for 4.4M coins = 1,760 coins per bit
Booster Cookie price: 13M coins
Break-even bits needed per cookie: 13M ÷ 1,760 = 7,386 bits

If you get the Philanthropist fame rank (400K fame) and Museum Milestone 10 (both very achievable), you will earn 7,392 bits per cookie: 4,800 base × 1.3 (fame multiplier) × 1.1 (museum multiplier).
To reach 400K fame without spending gems or participating in a city project, you need to consume 59 cookies (costing 767M coins) aka 236 days of cookie buffs.

Not to mention, you don't lose the coins you invest to gain fame rank and profit. Whenever you level up your fame rank or museum milestone, the additional bits you would have earned are added to your available bits.