35 watts at 800MHz mere inches from the head of anyone in the back seat is stupid. With so many other options, even for covert, it sounds more like a lazy installer.
Many years ago when we were getting ready to reband our 800MHz system, we had to inventory all the radios.
Our transit agency had decided somewhere along the way that they could get the local stereo shop to install the radios much cheaper than the 2 way radio shop...
We were on a bus getting the serial number off the radio and we couldn't find the antenna. We searched all over, up on a ladder, etc. Finally we started pulling on the coaxial cable. Some dumb a. installer had taken the NMO mount, 800MHz antenna and all the excess cable, wadded it up in a ball and zip tied it in the overhead area above the driver.
Had a talk with the maintenance supervisor about how stereo installation and radio installation are differnt skill sets.
So, no, this isn't surprising at all. I'd be willing to bet there is some connection to a stereo installation there somewhere. Either done at a shop or by an ex-stereo installer.