What working on SaaS billing taught me about token-based vs subscription pricing for AI products

At Saaslogic, we work closely with SaaS billing infrastructure across growth-stage products. One pattern keeps showing up: AI SaaS founders defaulting to subscription pricing and quietly breaking their margins under usage variance. It's not laziness. Subscription pricing is familiar, easy to sell, and simple to implement. But for AI products specifically, it creates a structural problem that compounds as you scale and by the time most founders notice it, they've already frustrated a chunk of their best customers. Here's what I've learned from being close to this problem daily. The core issue with subscriptions for AI products Subscription pricing was designed for software with relatively flat infrastructure costs. A project management tool, a CRM, an email platform, your costs don't change much whether a user logs in twice a week or twenty times. AI products break this assumption completely. Every inference call, every document processed, every image generated consumes variable compute