You don't have to pay the full £36 pounds, you can pay £24, £12 or if you want the demo, nothing. Also, Live For Speed is a simulation not a game, fair enough there are some unrealistic parts like crashes and the tyre physics but one of them is being worked on and the other is not any more unrealistic than iRacing or rFactor's versions.
As expr said, if you think the game is old and out dated, why bother? Play Automobilista or rFactor 2 if you want a good sim.
"when for that price you can pretty much buy a modern 2015-2016 racing simulator" Yeah but don't forget about all those DLCs you need to buy to keep racing on the more populated servers and those licenses you need to renew... Claiming that LFS has a bad price compared to other sims is like claiming that Usain Bolt isn't a good sprinter, it just isn't true.