Again, you don't really have a point. If someone *wants* to use a toll express lane every day that's their decision. Rational people understand that it's not always worth paying just to avoid congestion.
… it is their decision, you’re correct. Someone with a higher income, who is more easily able to afford the higher toll cost, is more likely to use that lane, particularly on a regular basis, than someone who cannot afford it. Of course one off instances, such as the daycare example, or running late to an important event, will occur that will prompt the average middle / lower class person to pay it, but they won’t be a regular user.
The more income you have, the less the toll price becomes that noticeable to deter you away. It’s a small expense that may be negligible. When you have a lower income and every dollar counts, you cannot afford to pay that toll and it will make a difference.