One of the benefits of the Mariners mid-market size is that they can absorb bad contracts for short periods of time in order to improve the haul of prospects they can get back. For example, by being able to take on the bad contracts of Jay Bruce and Anthony Swarzak, it allowed them to unload an even worse contract in Robinson Cano.
This option of basically “buying” better trade packages is not a luxury the teams like Tampa Bay or Oakland can afford when they go about rebuilding their rosters. The Mariners can.