There are various stories as to how crisps came to be invented, one of these being that a man dining in a restaurant in the USA in the 19th century kept sending his fried potatoes back to the kitchen because thay were too fatty/soggy. The chef kept cutting them more thinly until the customer was satisfied. Believe that if you like!
What is sure, however, is that 'flavoured' crisps are a much more recent creation. Given that the earliest recorded appearance of the word 'rozzer' to mean 'policeman' was in the 1890s...long before bacon-flavoured crisps existed...there is no chance that that is the word's source.
Folk etymology is alive and well still!