Dad worked for Esso, 40 years.  

All gas is not equal and one does not require a high performance rig to be affected by cheap gas.  
One does not have to always use the expensive stuff, but an occasional run through of the expensive stuff will have an effect.

To further the analogy, I don't drive a Labourghini.  I drive a 10 year old Pontiac.  It failed a required emissions test.  I bought a mickey of engine cleaner (Guanteed Pass) and followed the instructions.  Passed the emissions test.

Gas degrades over time.  Last year's cheap fuel may cause more gunk to build up than a new can of cheap fuel.


The real answer here is to get a Trangia and avoid the whole issue completely.   ;)