Variation of prices at local model shops

[budfish]

I run a laser zx5 fs2 and recently I needed to change my slipper pads so I went to my local model shop which is Je spares the price of a set of pads £12.87 my next local shop is Ross mods which do the same parts for £8.99 that's a £3.88 difference why could this be? so upon checking further I found the spur gear for my laser is £1 cheaper at Ross mods than at Je spares it dos'nt sound a lot but on £5 part it's 20% I have spent well over £1000 at Je spares and if I could have saved an average of 20 % I would be £200+ richer in one year
Springs for my laser £5.75 at Ross mods at Je £6.90
£7 difference in a pair of drive shafts seems the price difference is across the board

Why the huge difference in price ? Any ideas

Buds