Probably because you could sink 5+k into it super easily and it would make sense to buy a 18-20k car with better milage and a record of full maintenance.
Bearings, Water pump, disks and pads all round, tyres, engine and gearbox mounts, it will need new suspension all round at that milage. Sounds like a clutch and flywheel... Will it need an inspection? etc
Those are just top level things that's not including paint condition and other gremlins...
A decent coupe is like 20-22k at what half the milage 60-65k so really will all the above you would be about the same with 120k+ miles.
Ive had mine 2 years and spent 5k on it so far and it was a good condition 63k miler...