Many games are initially entered as TBA because the teams are not yet known. When editing the game to input the correct teams later on, the site changes to the first site listed as soon as the home team changes.
The site needs to stay as it is because the teams do not necessarily play at the same location at all times.
This automatically changing creates extra unnecessary clicks and potentially a problem if interrupted while making a change and save it while the site gets overlooked and then officials show up at the wrong location. HUGE problem.