You can get cheap stuff pretty easy.. I've bought some myself it was sh1t and didn't fit.
As someone who sells and buys stuff for my own car I do understand a little where you are coming from, but you can say the same thing about a packet of crisps, a pair of trainers, a car. The actual cost of something to make may be cheap but the hidden costs are huge.
Ask RT, Falcon, Abbey, Clark, CS etc what it costs in wages, rent, insurance, websites blah blah and you will probably be surprised what they need to turnover just to survive, we all would like every business in every sector to sell us stuff at the same price as it cost them to make the product but if that was to happen they wouldn't be a business for very long.
Incidentally I have some spoilers coming in at around £150 so don't take offense at what I wrote above as I could do with some sales