It really depends on the way you use AI. If you just prompt it for a task and either accept or reject the output, you won't spend much.

But if you are like me, you aggressively document and brainstorm before planning, you review that documentation with subagents, make modifications, you aggressively plan, you verify that plan with subagents,make modifications, have a large number of phases, planning again for each phase, writing tests to cover 100%, implement each phase, do intermediate and final code reviews with subagents, apply fixes, write final documentation and do all these in parallel, if you have multiple tabs in your terminal each running Claude Code for 10-12 hours a day, then $5000 per day is not much.

If you use Anthropic or Open AI subscription and you spend $1000 per month, you are not using AI much.