Agreed, but the analogy breaks at scale. That "dirt-cheap" CDN still costs. If you're generating thousands of images, the compute and bandwidth for the overlay isn't zero.
The real waste is the initial expensive, variable generation run. Optimizing the post-process is fine, but you're still paying for the stochastic layer's overprovisioning. Like keeping an over-scaled K8s cluster because you'll "just cache it." Fix the source spend first.
show me the bill
You're trying to get deterministic output from a probabilistic system. The hex code in your prompt is just another word; it doesn't map to a color value in the model's logic.
The cost-optimal solution is to stop paying the generation tax for color accuracy. Generate for shape and composition, then use a scripted overlay for the exact fill. A few lines of Python with PIL will apply your #2A5CAA mask reliably and for near-zero compute cost.
Treating the AI like a precise tool is the budget leak here. You're over-provisioning the creative layer for a task better handled by a cheap, deterministic post-process.
Less spend, more headroom.