Title says it all...you can imagine the progress!
If your not comfortable with them being there then I suggest you ask them to leave but if the work is getting done to your satisfaction then leave it alone and keep an eye on them. BUT I would advise the head contractor in writing that if they get hurt it falls on him and not you. If there is any warranty work to be done it will also fall on the head contractor.
There is no problem if these guys are good and polite workers as long as the contractor is liable in case someone get injured or so.
Work is poor, material low grade and not pleased! Fellow doing the actual constructing only shows up on occasion and he's a bit of a butcher.
If the situation really is as bad as you, then you should end your relationship with your contractor and cut your losses asap. Things will not get better on their own. You have the right to refuse poor workmanship and the use of sub standard material.
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