Film unions don't regulate indie films — hopefully this will be much the same.
Large budget films use unions because we are the only ones skilled enough to do it properly & professionally; you just can't find 200 non-union to pull it off, not without someone getting hurt in the process, or having a terrible end result
A Tier-1 has benefits such as $108/day toward healthcare, retirement. Pay rates in the range of $21-26/hr.
That said, i know of plenty of super-low budget indies that are just too small to use the contract -- the union often doesn't mind, and union workers will still do these 'passion projects' because they love the work