yeah if they didnt want large awesome oak trees, they could have planted different trees there. like some crappy pears that are way cheaper than oaks, and much shorter lived.
also they would not necessarily tear up the concrete. If given lots of space which oaks need, (and there are long wide tree lawns where these oaks are planted) the trees will only grow where the resources are. Trees are opportunistic and want to survive while putting out the least amount of energy possible. While some species have more aggressive root systems (red and norway maples are high on the list), oaks are not one of these.
Anyway, end tree rant. If you want to get more details feel free to contact me off line…. it just happens to be what I spend most of my ‘professional time’ doing.
one reason trees tear up sidewalks aside from being aggressive/wrong tree in wrong space is that sidewalk construction as it currently exists allows for condensation to form under the top block of concrete, and then the tree roots grow towards that water supply. there are a lot of ways to keep that from happening.. which i can also elaborate on in pm or email