It's a lot of trouble and expensive to set up a proper rig and the return on investment can take a long time when mining. It's not as cheap or profitable to mine the coins as you make it seem.
This online calculator:
allows you to enter electricity cost, energy consumption and hashing power of specific rigs to figure out how much you'd make. It takes into account total network hashing power, average block time etc.
An antminer S9 (currently viewed as being the best pro-sumer miner on the market) has a hashing power between 12 and 14 TH/s and consumes between 1200 and 1400 Watts of power. at an average electricity price in the US of $0.12 per kW/h (and Europe's avg price is between 12 and 18 cents) you can expect to profit just a little under $500 per month on the machine.
Those machines are sold out direct from the manufacturer but you can find them from resellers on amazon or eBay for between $5000 and $7000 depending which batch they were from. It would take you a year to make your money back on your investment, and since the nature of that playing field is that a piece of equipment's yields reduce over time it will most likely take a lot more than one year to break even from the purchase of that miner.
Most miners are pretty much the same or take even longer to pay back; feel free to play around with that calculator and input different mining rigs you find on the internet.
Renting Servers: this site, the top result in a google search,
https://www.nicehash.com/buy will rent you 50TH/s of hashing power, for 24 hours, for ~$94USD (they charge in Bitcoin). Using the calculator I linked above 50TH/s and an electricity cost of $0 would yield $2447/month worth of bitcoin or just over $81/day. So you'd be giving them $94 for $81 worth of Bitcoin.
Bottom Line: the reason people don't easily mine it for a tenth of the cost is because it's neither easy nor much cheaper to mine it.