I'm surprised that you're surprised

I generally don't bother adding things that will never be seen, especially with tracks that are a lot of work to put together. Here's how I did the tracks on
my recent K2 Black Panther, for example:
Notice I also didn't bother to paint the part of the track that touches the ground
Lining up wheel arms is not usually difficult if you make sure the front and last are glued in the correct position. Leave the others off for now and let the glue dry. Then add the remaining arms and either place a ruler across the axles, that you can use to press them all into line with (resting on the front and rear axles), or set the model on a glass plate and push all the arms so they touch the glass. You can't use the plate if there are protrusions on the undersides of some of the suspension arms but not all of them, though.
No, because I suspect I will end up breaking the track as I handle it after the glue has dried, and I foresee trouble painting between the wheels and tracks.
My main reason for favouring workable tracks these days is because I can reach everything with paint and still fit the track properly to the model.