My theory is the rich teams are loading up while they can because they expect significant changes to the salary/payroll system after the expected lockout next season.

If there was a hard cap instituted it probably wouldn’t come into effect for a couple years and there may be some grace for existing contracts. Even if there isn’t a hard cap, if they change the luxury tax rules or eliminate deferrals teams would rather do short term huge dollar deals until they see how it shakes out.