I was told by a specialist shop that most factory done structuring isn't great, a proper grind might make a difference.
Shops are in the business to create revenue. A good way to create revenue is to sell goods and services to people even if they don't need them. This is especially true if you need to pay for specialty equipment like base grinders and sturcturing tools.
That being said, the factory structure may not be ideal for someone's riding conditions and a different structure could benefit them i.e. you pick up a new board in the spring and are going to be riding summer slush. The factory structure isn't ideal for slush, but is it really worth getting new structure cut that will need to be recut the next winter?