Yeah, we compelled in our franchise agreement to use the head office specified and approved equipment.
I don't think it's necessarily motivated by corporate greed.
In fact head office stood to lose the most from the decision.
The franchisee benefits financially as he is using less gas, not replacing volcanic rock every 3 months, purchasing less cleaning material etc etc etc
Unfortunately if sales are down, head office gets less royalties, the franchisee lower profits and worse case scenario, a failed business which benefits no one.
With the new grill you get out what you put in. What head office needs to do is tweak their pattie recipe slightly! Extra seasoning perhaps or a different spice! We use a lovely basting in the kitchen on our ribs. Basting the patties just before they go off the grill would go alone way towards adding something "authentic" to the flavour!