The ongoing project to replace the entire upper level roadway decking -- which began in 2012 and is supposed to be completed next year -- cost $82 million by itself.
The next major project to be undertaking on the bridge will involve the rehabilitation of the cable support system and the replacement of all the suspender cables (there are about 600 of them). The price tag on that project is approximately $1 billion.
You don't just build a bridge and walk away from it. It costs a fortune to keep it in good working order when it's more than 80 years old.
It costs money to keep roads in working order too, but most roads in the US don’t have tolls. That’s what taxes in general are for.
Also, the GWB generates $1.5 million in revenue a DAY. That’s more than a half a billion a year. That dwarfs the costs you mentioned, which, by the way, aren’t incurred every year. So stuff it.