Work to live, don't live to work. Personally, I'd rather live comfortably at all times and make enough to "get by" rather than bust my ass off to make more money.
I guarantee you you're not living very comfortably off of $12 an hour. $12 versus $25 is actually pretty close to the definition of struggling to get by versus being able to live comfortably. Good luck paying rent/mortgage, utilities, phone, Internet (so you can read reddit), food, insurance, car payment, and car insurance on less than $25k a year before taxes. Then have fun having any left over for any sort of recreation, vacation, hobbies, etc. Besides, just because you apparently don't like labor intensive work doesn't mean nobody does. I know people who like construction work. I know people who enjoy mechanic work. Before my current job, I enjoyed "busting my ass" building, carrying, and installing heavy cabinets. I enjoyed doing flooring, instilling drywall, etc.
We also have to look at what type of work we're referring here to, there could be a possibility of receiving raise(s) which can equate to much more money down the line, rather than working for $25 but you then reach a cap in your industry.
Sure, but now you're talking about hypotheticals that weren't in your original post. If that's the case, then we can look at my dad who didn't finish high school, worked doing kitchen custom cabinet and wood work, and eventually went into business for himself. That took his $25 industry cap job up to him making $110-150k a year.
As for your body being more likely to give out, that's pretty debatable. Most people I see working desk jobs are unhealthy as hell. Our bodies aren't meant to sit around in a chair all day. Being physically active at work guarantees you're being physically active, it takes a lot of conscious effort to make sure you're active enough when you have a job that doesn't require much movement.
Being able to read well is definitely a great thing, and I wouldn't want to be illiterate. If somebody went from being locked up to having a $25 an hour job though, then I can't really fault them in taking that route. That's a very livable income in most of the US.