As a non-gym goer (if I had the money...), what injuries are you talking about? I can guess that gyms want to protect people who try to lift more weight than they can, rather than straining from posture.

> As a non-gym goer (if I had the money...), what injuries are you talking about?

The problem with Smith Machines is that the movements are all linear, e.g. perfectly straight. NOTHING in your body moves in a perfectly straight line, there is an arc to almost everything you do.

Frequently people do squats with smith machines which will eventually hurt their backs from bad form.

(Indeed, I wince in pain sometimes watching people do horrible things to their backs in smith machines, holy crap!)

Now you CAN do things wrong with barbells of course, but many of the things done with a smith machine cannot be right at all!

> (if I had the money...),

My small local gym costs $200 a year.

Find a small local neighborhood gym (even if it isn't in your neighborhood!), they are always affordable!

And hey, body weight exercise programs are free. :)