This echoes a common misconception about best guns, that they were made for wealthy titled people. The makers' ledgers disprove this notion. The plain Mr's and mid level armed forces ranks far outnumber the nobility. Best guns were affordable back then.
I think you misunderstand British society at that time (early 20th Century). Titled people at that time were suffering a decline in wealth. For many, much of their wealth had come from overseas interests in the so called 'British Empire' - sugar, tea, rubber, guano, cotton, tobacco etc. This had much declined as the 'Empire' had shrunk. At home money had mainly come from either agricultural (much of that in rents) and some from industry, but the industrialists were often 'new' money and not titled. After WW1 this became even more so with agriculture in depression and many former 'Empire' areas of the world being more independent, if not yet totally independent (much of that came after WW2).
There were many, many business people (law, industry, shipping, 'city' (like stockbrokers and banking families) who were wealthy, but not titled. They would often have bought from the 'best' makers, but would appear in the gunmakers books as plain Mr. xxx.
I have read that certain makers tended to have a following amongst certain 'communities' the example springing to mind being Henry Atkin, who seemed to have a larger than usual following from banking families. I have also hear it said that Cogswell and Harrison were popular with the military.
Remember also that in the UK (until the late 20th century) many people who served in the military as officers came from wealthy families and it was common practice to retain the title of the military rank on retirement. Where I live, my fathers generation had several Colonels and Majors (Army) and Admirals, Commanders and Captains (Royal Navy) who had long been out of the armed forces, but retained their title in either retirement, or their civilian lives.
Your comment of prices against income is also very relevant. In real terms, motor vehicles, cameras/photography, radio/television most domestic appliances (washing, dishwashing, cleaning, refrigeration) have decreased markedly in real terms - whereas (in the UK anyway) houses/property, professional services (legal, medical and financial) have increased. 'Best' guns fall firmly into the increased category. Guns overall (mainly imports) much more holding line with incomes.
