For Sale: Fixed gear mercier 26"

IMHO not originally a fixed gear - note hanger for rear deraillieur, empty holes for cable on rear stays and silver bit for a lever on top tube. Apart from lack of track ends of course.

You're right it's not a track bike. It's a fixed gear training bike for use on the road.
It's not pretending to be anything other than a winter training bike for use in the off season.
Racers used to use them on the road for training cadence. It's from a time before it became trendy to ride a fixed gear bike.
It's a piece of cycling history.
You'll find out that there are lots of modern and classic road bike frames that have been converted to fixed gear bikes. Some more creative owners use angle grinders to remove gear hangers and braze on's to make their road bikes look more like a track bike.

Nite Nite............