Do not think lawyers get paid weekly. Usually it is a percentage of what the settlement money has been awarded. Of course, lawyers get hired by a client so that brings in money, as well a some people who keep a lawyer on retainer. They make good money- the better they are and the more wins they have- the more money the make.
At the firm I work at, they have a base salary, (they get paid bi-weekly) and then they get a percentage of all the expenses, billable & hourly work. Some attorneys charge in 15 minute increments also. Then of course, if they win a case they get a percentage of that. A retainer is just a "down payment" for the work the attorneys do, which is put in an account and used along the way as work is done.