Convenient for those who are alert to the charges they may incur when using a toll road.
You did not get caught up in anything. If you had read your contract I am sure the charge is explained. In addition you intentionally got on a road for which you have to pay.
Your post should be thanking Budget for doing you a favor and dropping the legitimate charge.

This is from Budgets website

"In the state of Florida the renter has the option of using Sun-Pass Only, ePass Only, and Leeway high-speed lanes. When a renter utilizes these high-speed toll lanes, the toll system identifies the car and charges the standard non-discounted fee for toll roads as published by the toll authority plus the convenience fee of $2.50 per day and $10.00 per week based on the length of the car rental. The fee will be posted to the credit card you used on your rental."

It has been discussed on most of the car rental forums as well

Now you could have been inconvenienced and taken a less direct route but you chose the toll road and it convenience to you. You should have paid the fee.
People should take responsibility for their actions or inactions not blame companies that charge fees you should be aware of. This not a hidden fee.