First of all, AAA games refer to games made by massive studios (usually numbering up to 10,000 people and above). These games have budget of over $100 million.
On the other hand, indiegames are made by a small team of people with a smaller budget.
In my opinion,it would be unreasonable for indiegames to cost as much as AAA games because
AAA games have a higher level of graphics
AAA games have multiple hours of gameplay which could make their games take days to complete
AAA need to charge more to generate more money because of its large payroll