It's all BS. My car only goes in for warranty work, when & if required. Otherwise, I manage all fluid changes and such for all my vehicles. When the warranty expires, then I'll fix it myself or outsource it to the appropriate shop. For $120, I'm sure all they do is dump a $8 fuel system cleaner into the tank. One Toronto shop was caught for this, along with printing fraudulent emission test papers; they're no longer in business.
'11 Ram SXT 4x4 quad cab - 5.7L V8; 128,200kms
'09 Malibu 2Lt 3.6L - 140,000kms purchased 1 March 2019
'06 Pontiac G6 GT - 3.5L V6; 162,000kms (rear ended 15 Feb 2019, and given totalled title by insurance)